The condition in which reasonable knowledge regarding risks, benefits, or the future is not available.
A theorem in probability theory named for Thomas Bayes (1702-1761). In epidemiology, it is used to obtain the probability of disease in a group of people with some characteristic on the basis of the overall rate of that disease and of the likelihood of that characteristic in healthy and diseased individuals. The most familiar application is in clinical decision analysis where it is used for estimating the probability of a particular diagnosis given the appearance of some symptoms or test result.
Statistical formulations or analyses which, when applied to data and found to fit the data, are then used to verify the assumptions and parameters used in the analysis. Examples of statistical models are the linear model, binomial model, polynomial model, two-parameter model, etc.
Laboratory tests demonstrating the presence of physiologically significant substances in the blood, urine, tissue, and body fluids with application to the diagnosis or therapy of disease.
Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.
In statistics, a technique for numerically approximating the solution of a mathematical problem by studying the distribution of some random variable, often generated by a computer. The name alludes to the randomness characteristic of the games of chance played at the gambling casinos in Monte Carlo. (From Random House Unabridged Dictionary, 2d ed, 1993)
A theoretical technique utilizing a group of related constructs to describe or prescribe how individuals or groups of people choose a course of action when faced with several alternatives and a variable amount of knowledge about the determinants of the outcomes of those alternatives.
The process of making a selective intellectual judgment when presented with several complex alternatives consisting of several variables, and usually defining a course of action or an idea.
A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.
Computer-based representation of physical systems and phenomena such as chemical processes.
A method of comparing the cost of a program with its expected benefits in dollars (or other currency). The benefit-to-cost ratio is a measure of total return expected per unit of money spent. This analysis generally excludes consideration of factors that are not measured ultimately in economic terms. Cost effectiveness compares alternative ways to achieve a specific set of results.
The measurement of radiation by photography, as in x-ray film and film badge, by Geiger-Mueller tube, and by SCINTILLATION COUNTING.
A measurement index derived from a modification of standard life-table procedures and designed to take account of the quality as well as the duration of survival. This index can be used in assessing the outcome of health care procedures or services. (BIOETHICS Thesaurus, 1994)
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
A stochastic process such that the conditional probability distribution for a state at any future instant, given the present state, is unaffected by any additional knowledge of the past history of the system.
Computer-assisted mathematical calculations of beam angles, intensities of radiation, and duration of irradiation in radiotherapy.
The study of chance processes or the relative frequency characterizing a chance process.
Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.
Statistical models of the production, distribution, and consumption of goods and services, as well as of financial considerations. For the application of statistics to the testing and quantifying of economic theories MODELS, ECONOMETRIC is available.
The qualitative or quantitative estimation of the likelihood of adverse effects that may result from exposure to specified health hazards or from the absence of beneficial influences. (Last, Dictionary of Epidemiology, 1988)
The use of an external beam of PROTONS as radiotherapy.
Any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). It may result from natural factors such as changes in the sun's intensity, natural processes within the climate system such as changes in ocean circulation, or human activities.
Application of statistical procedures to analyze specific observed or assumed facts from a particular study.
The protection, preservation, restoration, and rational use of all resources in the total environment.
Mathematical or statistical procedures used as aids in making a decision. They are frequently used in medical decision-making.
Functions constructed from a statistical model and a set of observed data which give the probability of that data for various values of the unknown model parameters. Those parameter values that maximize the probability are the maximum likelihood estimates of the parameters.
The collective name for the republics of ESTONIA; LATVIA; and LITHUANIA on the eastern shore of the Baltic Sea. (Webster's New Geographical Dictionary, 1988, p111)
The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.
Psychophysical technique that permits the estimation of the bias of the observer as well as detectability of the signal (i.e., stimulus) in any sensory modality. (From APA, Thesaurus of Psychological Index Terms, 8th ed.)
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
Mistakes committed in the preparations for radiotherapy, including errors in positioning of patients, alignment radiation beams, or calculation of radiation doses.
Processes that incorporate some element of randomness, used particularly to refer to a time series of random variables.
Approximate, quantitative reasoning that is concerned with the linguistic ambiguity which exists in natural or synthetic language. At its core are variables such as good, bad, and young as well as modifiers such as more, less, and very. These ordinary terms represent fuzzy sets in a particular problem. Fuzzy logic plays a key role in many medical expert systems.
The prediction or projection of the nature of future problems or existing conditions based upon the extrapolation or interpretation of existing scientific data or by the application of scientific methodology.
A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.
The total amount of a chemical, metal or radioactive substance present at any time after absorption in the body of man or animal.
Elements of limited time intervals, contributing to particular results or situations.
The longterm manifestations of WEATHER. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)
The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)
Three-dimensional computed tomographic imaging with the added dimension of time, to follow motion during imaging.
Works about clinical trials that involve at least one test treatment and one control treatment, concurrent enrollment and follow-up of the test- and control-treated groups, and in which the treatments to be administered are selected by a random process, such as the use of a random-numbers table.
Any deviation of results or inferences from the truth, or processes leading to such deviation. Bias can result from several sources: one-sided or systematic variations in measurement from the true value (systematic error); flaws in study design; deviation of inferences, interpretations, or analyses based on flawed data or data collection; etc. There is no sense of prejudice or subjectivity implied in the assessment of bias under these conditions.
Expectation of real uncertainty on the part of the investigator regarding the comparative therapeutic merits of each arm in a trial.
Signals for an action; that specific portion of a perceptual field or pattern of stimuli to which a subject has learned to respond.
Evaluation of biomedical technology in relation to cost, efficacy, utilization, etc., and its future impact on social, ethical, and legal systems.
The exposure to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals.
A plant genus of the family ASTERACEAE that is used in folk medicine as CHAMOMILE. Other plants with similar common names include MATRICARIA; TRIPLEUROSPERMUM and ANTHEMIS.
Theoretical representations that simulate the behavior or activity of genetic processes or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.
The effect of GLOBAL WARMING and the resulting increase in world temperatures. The predicted health effects of such long-term climatic change include increased incidence of respiratory, water-borne, and vector-borne diseases.
The body of truths or facts accumulated in the course of time, the cumulated sum of information, its volume and nature, in any civilization, period, or country.

Health outcomes and managed care: discussing the hidden issues. (1/927)

Too often the debate over health outcomes and managed care has glossed over a series of complex social, political, and ethical issues. Exciting advances in outcomes research have raised hopes for logical medical reform. However, science alone will not optimize our patients' health, since value judgements are necessary and integral parts of attempts to improve health outcomes within managed care organizations. Therefore, to form healthcare policy that is both fair and efficient, we must examine the fundamental values and ethical concerns that are imbedded in our efforts to shape care. We must openly discuss the hidden issues including: (1) trade-offs between standardization of care and provider-patient autonomy; (2) effects of financial incentives on physicians' professionalism; (3) opportunity costs inherent in the design of insurance plans; (4) responsibilities of managed care plans for the health of the public; (5) judicious and valid uses of data systems; and (6) the politics of uncertainty.  (+info)

Impact of therapeutic research on informed consent and the ethics of clinical trials: a medical oncology perspective. (2/927)

PURPOSE: To create a more meaningful understanding of the informed consent process as it has come to be practiced and regulated in clinical trials, this discussion uses the experience gained from the conduct of therapeutic research that involves cancer patients. DESIGN: After an introduction of the ethical tenets of the consent process in clinical research that involves potentially vulnerable patients as research subjects, background that details the use of written consent documents and of the term "informed consent" is provided. Studies from the cancer setting that examine the inadequacies of written consent documents, and the outcome of the consent process itself, are reviewed. Two ethically challenging areas of cancer clinical research, the phase I trial and the randomized controlled trial, are discussed briefly as a means of highlighting many dilemmas present in clinical trials. Before concluding, areas for future research are discussed. RESULTS: Through an exclusive cancer research perspective, many current deficiencies in the informed consent process for therapeutic clinical trials can be critically examined. Also, new directions for improvements and areas of further research can be outlined and discussed objectively. The goals of such improvements and research should be prevention of further misguided or ineffective efforts to regulate the informed consent process. CONCLUSION: To ignore this rich and interesting perspective potentially contributes to continued misunderstanding and apathy toward fulfilling the regulatory and ethically obligatory requirements involved in an essential communication process between a clinician-investigator and a potentially vulnerable patient who is considering clinical trial participation.  (+info)

Towards a feasible model for shared decision making: focus group study with general practice registrars. (3/927)

OBJECTIVES: To explore the views of general practice registrars about involving patients in decisions and to assess the feasibility of using the shared decision making model by means of simulated general practice consultations. DESIGN: Qualitative study based on focus group interviews. SETTING: General practice vocational training schemes in south Wales. PARTICIPANTS: 39 general practice registrars and eight course organisers (acting as observers) attended four sessions; three simulated patients attended each time. METHOD: After an introduction to the principles and suggested stages of shared decision making the registrars conducted and observed a series of consultations about choices of treatment with simulated patients using verbal, numerical, and graphical data formats. Reactions were elicited by using focus group interviews after each consultation and content analysis undertaken. RESULTS: Registrars in general practice report not being trained in the skills required to involve patients in clinical decisions. They had a wide range of opinions about "involving patients in decisions," ranging from protective paternalism ("doctor knows best"), through enlightened self interest (lightening the load), to the potential rewards of a more egalitarian relationship with patients. The work points to three contextual precursors for the process: the availability of reliable information, appropriate timing of the decision making process, and the readiness of patients to accept an active role in their own management. CONCLUSIONS: Sharing decisions entails sharing the uncertainties about the outcomes of medical processes and involves exposing the fact that data are often unavailable or not known; this can cause anxiety to both patient and clinician. Movement towards further patient involvement will depend on both the skills and the attitudes of professionals, and this work shows the steps that need to be taken if further progress is to be made in this direction.  (+info)

Ethnicity, bioethics, and prenatal diagnosis: the amniocentesis decisions of Mexican-origin women and their partners. (4/927)

Bioethical standards and counseling techniques that regulate prenatal diagnosis in the United States were developed at a time when the principal constituency for fetal testing was a self-selected group of White, well-informed, middle-class women. The routine use of alpha-fetoprotein (AFP) testing, which has become widespread since the mid-1980s, introduced new constituencies to prenatal diagnosis. These new constituencies include ethnic minority women, who, with the exception of women from certain Asian groups, refuse amniocentesis at significantly higher rates than others. This study examines the considerations taken into account by a group of Mexican-origin women who had screened positive for AFP and were deciding whether to undergo amniocentesis. We reviewed 379 charts and interviewed 147 women and 120 partners to test a number of factors that might explain why some women accept amniocentesis and some refuse. A woman's attitudes toward doctors, medicine, and prenatal care and her assessment of the risk and uncertainty associated with the procedure were found to be most significant. Case summaries demonstrate the indeterminacy of the decision-making process. We concluded that established bioethical principles and counseling techniques need to be more sensitive to the way ethnic minority clients make their amniocentesis choices.  (+info)

Autonomy, rationality and the wish to die. (5/927)

Although suicide has traditionally carried a negative sanction in Western societies, this is now being challenged, and while there remains substantial public concern surrounding youth and elder suicide, there is a paradoxical push to relax the prohibition under certain circumstances. Central to the arguments behind this are the principles of respect for autonomy and the importance of rationality. It is argued here that the concepts of rationality and autonomy, while valuable, are not strong enough to substantiate a categorical "right to suicide" and that the concepts of "understandability" and "respect" are more useful and able to provide the foundation for responding to a person expressing a wish to die. Roman suicide, sometimes held as an example of "rational suicide", illustrates the effects of culture, tradition and values on the attitudes to, and the practice of, suicide.  (+info)

Fraud, misconduct or normal science in medical research--an empirical study of demarcation. (6/927)

OBJECTIVES: To study and describe how a group of senior researchers and a group of postgraduate students perceived the so-called "grey zone" between normal scientific practice and obvious misconduct. DESIGN: A questionnaire concerning various practices including dishonesty and obvious misconduct. The answers were obtained by means of a visual analogue scale (VAS). The central (two quarters) of the VAS were designated as a grey zone. SETTING: A Swedish medical faculty. SURVEY SAMPLE: 30 senior researchers and 30 postgraduate students. RESULTS: Twenty of the senior researchers and 25 of the postgraduate students answered the questionnaire. In five cases out of 14 the senior researchers' median was found to be clearly within the interval of the grey zone, compared with three cases for the postgraduate students. Three examples of experienced misconduct were provided. Compared with postgraduate students, established researchers do not call for more research ethical guidelines and restrictions. CONCLUSION: Although the results indicate that consensus exists regarding certain obvious types of misconduct the response pattern also indicates that there is no general consensus on several procedures.  (+info)

Live attenuated vaccine trials in medically informed volunteers: a special case? (7/927)

A group of activist clinicians have offered to volunteer for clinical trials of live attenuated HIV vaccines. This has provided an important conceptual challenge to medical ethics, and to work on the development of HIV vaccines. In exploring these issues, this article highlights how the HIV field has altered the content as well as the tone of ethical discourse. The balance of expertise and authority between research subjects and triallists is profoundly changed, raising questions about the limits of voluntarism and differing perspectives on risk-benefit analysis. Care is needed to ensure that the novelty of the situation does not confuse the central ethical and scientific issues.  (+info)

The man who claimed to be a paedophile. (8/927)

A psychiatrist recounts a case of a man presenting with severe depression who claimed to have abused children and his pet dog. Clinical management of the case hinged on whether this claim was true, a lie or delusional. The uncertainty over this raised complex ethical dilemmas regarding confidentiality and protection of the public (and animals).  (+info)

Sylvain Mazuel, Chantal de Fouquet, Jean-Paul Chilès, Patrick Goblet, Mohamed Krimissa. Geostatistical modelling for the quantification of uncertainties on the unsatured zone and the groundwater transfer. Groundwater hydraulics in complex environments, Jun 2006, Toulouse, France. pp.2. ⟨hal-00599172⟩ ...
The death of Justice Ruth Bader Ginsburg has cast fresh uncertainty on the fate of the Affordable Care Act as the Supreme Court prepares to hear arguments in a case challenging the constitutionality of the landmark health care law ...
Location: Philadelphia, Pennsylvania , Category: Disparities-focused. Diagnostic uncertainty, the perception of an inability to provide an accurate explanation of the patients health condition, increases the risk of diagnostic error in hospitalized patients if not communicated to families and across healthcare teams. Additionally, differences in clinician-patient communication have been implicated in health disparities in pediatric diagnosis. Improvements in the communication of diagnostic uncertainty have the potential to impact three primary drivers of diagnostic excellence: cognitive performance/diagnostic reasoning, patient/family engagement, and effective teamwork. The Childrens Hospital of Philadelphia will pursue understanding and identifying opportunities for improvement in the communication of diagnostic uncertainty in general pediatric patients admitted from the Emergency Department. Over nine months, they aim for a 20% improvement in the communication of diagnostic uncertainty to ...
TY - JOUR. T1 - Stochastic uncertainty analysis of damage evolution computed through microstructure-property relations. AU - Acar, Erdem. AU - Solanki, Kiran N.. AU - Rais-Rohani, Masoud. AU - Horstemeyer, Mark F.. PY - 2010/4/1. Y1 - 2010/4/1. N2 - Uncertainties in material microstructure features can lead to uncertainty in damage predictions based on multiscale microstructure-property models. This paper presents an analytical approach for stochastic uncertainty analysis by using a univariate dimension reduction technique. This approach is used to analyze the effects of uncertainties pertaining to the structure-property relations of an internal state variable plasticity-damage model that predicts failure. The results indicate that the higher the strain the greater the scatter in damage, even when the uncertainties in the material plasticity and microstructure parameters are kept constant. In addition, the mathematical sensitivity analysis results related to damage uncertainty are consistent ...
TY - JOUR. T1 - Reporting and analyzing statistical uncertainties in Monte Carlo-based treatment planning. AU - Chetty, Indrin J.. AU - Rosu, Mihaela. AU - Kessler, Marc L.. AU - Fraass, Benedick A.. AU - Ten Haken, Randall K.. AU - Kong, Feng Ming (Spring). AU - McShan, Daniel L.. PY - 2006/7/15. Y1 - 2006/7/15. N2 - Purpose: To investigate methods of reporting and analyzing statistical uncertainties in doses to targets and normal tissues in Monte Carlo (MC)-based treatment planning. Methods and Materials: Methods for quantifying statistical uncertainties in dose, such as uncertainty specification to specific dose points, or to volume-based regions, were analyzed in MC-based treatment planning for 5 lung cancer patients. The effect of statistical uncertainties on target and normal tissue dose indices was evaluated. The concept of uncertainty volume histograms for targets and organs at risk was examined, along with its utility, in conjunction with dose volume histograms, in assessing the ...
Classification of multispectral remotely sensed data with textural features is investigated with a special focus on uncertainty analysis in the produced land-cover maps. Much effort has already been directed into the research of satisfactory accuracy assessment techniques in image classification, but a common approach is not yet universally adopted. We look at the relationship between hard accuracy and the uncertainty on the produced answers, introducing two measures based on maximum probability and alpha quadratic entropy. Their impact differs depending on the type of classifier. In this paper, we deal with two different classification strategies, based on support vector machines (SVMs) and Kohonens self-organizing maps (SOMs), both suitably modified to give soft answers. Once the multiclass probability answer vector is available for each pixel in the image, we studied the behavior of the overall classification accuracy as a function of the uncertainty associated with each vector, given a ...
The impacts of the sea-ice characteristics distribution, roughness, temperature and thermal conductivity on an on-ice moving trough in the Fram Strait on 7 March 2002 are investigated. The situation is simulated with the mesoscale transport and fluid model METRAS and the named characteristics are varied within the range of observational uncertainty. The test cases are evaluated against aircraft measurements performed within the Fram Strait Cyclone Experiment 2002. The models sensitivity on the changes in sea-ice characteristics is quantified by statistical means. The strongest impacts on the near-ground temperature are found from sea-ice temperature, manifesting as an overall bias, and the positioning of the sea-ice edge, manifesting as a phase error. Only higher than natural homogenization of the sea-ice cover leads to some reduction of the amplitude error. A reduction of the sea-ice surface roughness is performed by applying an unrealistically small roughness length of z0= 1 mm. This ...
Presently there is no standard for the evaluation of measurement uncertainties for terrestrial laser scanner (TLS) despite the fact that the instrument has been on the market and used for a long time. Since the manufacturers specifications do not always correspond with reality, it is important to have knowledge about how well the instrument performs. Numerous studies over the past decade have applied different approaches to estimate the measurement uncertainties on various TLS.. The purpose of this study was to evaluate and compare the measurement uncertainties of the TLS Leica ScanStation C10 with the multi station Leica Nova MS50 under two different weather conditions. The uncertainty was calculated using ISO 17123-5:2012, which is an international standard developed for acquiring measurement uncertainties of total stations, to investigate whether this standard could also be applicable for TLS. The survey, which took place outdoor at the University of Gävle, was carried out by scanning ...
On-road transportation contributes 22% of the total CO2 emissions and more than 44% of oil consumption in the U.S. technological advancements and use of alternative fuels are often suggested as ways to reduce these emissions. However, many parameters and relationships that determine the future characteristics of the light-duty vehicle (LDV) fleet and how they change over time are inherently uncertain. Policy makers need to make decisions today given these uncertainties, to shape the future of light-duty vehicles. Decision makers thus need to know the impact of uncertainties on the outcome of their decisions and the associated risks. This paper explores a carefully constructed detailed pathway that results in a significant reduction in fuel use and greenhouse gases (GHG) emissions in 2050. Inputs are assigned realistic uncertainty bounds, and the impact of uncertainty on this pathway is analyzed. A novel probabilistic fleet model is used here to quantify the uncertainties within advanced vehicle ...
Bilinguals have distinct linguistic experiences relative to monolinguals, stemming from interactions with the environment and the individuals therein. Theories of language control hypothesize that these experiences play a role in adapting the neurocognitive systems responsible for control. Here we posit a potential mechanism for these adaptations, namely that bilinguals face additional language-related uncertainties on top of other ambiguities that regularly occur in language, such as lexical and syntactic competition. When faced with uncertainty in the environment, people adapt internal representations to lessen these uncertainties, which can aid in executive control and decision-making.. We overview a cognitive framework on uncertainty, which we extend to language and bilingualism. We then review two case studies, assessing language-related uncertainty for bilingual contexts using language entropy and network scientific approaches. Overall, we find that there is substantial individual ...
TY - JOUR. T1 - A novel approach to parameter uncertainty analysis of hydrological models using neural networks. AU - Shrestha, DL. AU - Kayastha, N. AU - Solomatine, DP. N1 - neotk. PY - 2009. Y1 - 2009. KW - Peer-lijst tijdschrift. UR - http://www.hydrol-earth-syst-sci-discuss.net/6/1677/2009. M3 - Article. VL - 6. SP - 1677. EP - 1706. JO - Hydrology and Earth System Sciences Discussions. JF - Hydrology and Earth System Sciences Discussions. SN - 1812-2116. ER - ...
TY - JOUR. T1 - A new didactic approach to statistical analysis of measurement data for the evaluation of measurement uncertainty - SAM-EMU. AU - Płowucha, W.. AU - Werner, T.. AU - Savio, E.. AU - Blunt, L.. AU - Jakubiec, W.. PY - 2012/12. Y1 - 2012/12. N2 - This paper describes assumptions, aims, methodology, content and consortium make up of a European project (SAM-EMU) founded under the Erasmus Lifelong Learning Programme. The project has developed learning materials in the field of evaluation of measurement uncertainty. It is available in the form of a multimedia web based course, which has many advantages. This format is commonly accepted as a good way to prepare an EU wide vocational training vehicle. The course is available in English.. AB - This paper describes assumptions, aims, methodology, content and consortium make up of a European project (SAM-EMU) founded under the Erasmus Lifelong Learning Programme. The project has developed learning materials in the field of evaluation of ...
Measurement Uncertainty Budget and ISO/IEC 17025 Accreditation Consulting for testing & calibration labs. FREE measurement uncertainty guide
A comprehensive framework for predicting response to therapy on the basis of heterogeneity in dceMRI parameter maps is presented. A motion-correction method for dceMRI sequences is extended to incorporate uncertainties in the pharmacokinetic parameter maps using a variational Bayes framework. Simple measures of heterogeneity (with and without uncertainty) in parameter maps for colorectal cancer tumours imaged before therapy are computed, and tested for their ability to distinguish between responders and non-responders to therapy. The statistical analysis demonstrates the importance of using the spatial distribution of parameters, and their uncertainties, when computing heterogeneity measures and using them to predict response on the basis of the pre-therapy scan. The results also demonstrate the benefits of using the ratio of Ktrans with the bolus arrival time as a biomarker.
This course provides software training to help geoscientists better understand the geological uncertainties in their 1D, 2D, or 3D petroleum system models. You will learn how to use PetroRisk, the uncertainty modeling tool within the PetroMod Basin & Petroleum Systems Modeling software package. PetroRisk assesses geological uncertainty and follows the entire migration path to provide probabilistic estimates for accumulations.. This course teaches you how to use the PetroMod* PetroRisk module to understand and quantify the uncertainties in your petroleum systems models. The course combines lectures on statistics and uncertainty analysis with practical exercises designed to show the impact of uncertainties in model input data. You will learn about dependencies and correlations between geological processes and model uncertainties.. This workshop is an elective component in the PetroMod Education Services offering. Students successfully completing this course will be able evaluate the impact of ...
Background The increasing use of the methods of evidence-based medicine to keep up-to-date with the research literature highlights the absence of high-quality evidence in many areas in psychiatry. Aims To outline current uncertainties in the maintenance treatment of bipolar disorder and to describe some of the decisions involved in designing a large simple trial. Method We describe some of the strategies of evidence-based medicine, and how they can be applied in practice, focusing specifically on the area of bipolar disorder. Results One of the key clinical uncertainties in the treatment of bipolar disorder is the place of maintenance drug treatments and their relative efficacy. A large-scale study, the Bipolar Affective DISORDER: Lithium Anticonvulsant Evaluation (BALANCE) trial, is proposed to compare the effectiveness of lithium, valproate and the combination of lithium and valproate. Conclusions Providing reliable answers to key clinical questions in psychiatry will require new approaches to
In this work, we examined the evolution of PET under future climate conditions. We also investigated to what extent seven different classical PET formulations could modify the partitioning of uncertainty associated with climate projections.
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NEW YORK Small business owners may be experiencing sticker shock now that insurers are revealing the rates they want to charge under the new health care law.
To conclusively determine whether aldosterone antagonists confer additional benefit on reducing SCDs in patients with ICDs, one would need to design a study in which patients with ICDs (and preferably a group without ICDs as well) were randomized to aldosterone antagonists versus placebo in addition to the usual heart failure medicines. Unfortunately, and to the best of our knowledge, such a study has not been performed. We have been able to obtain some observational retrospective data from MADIT II and the COMPANION trial that address this issue to some extent. We briefly present our findings, realizing that limitations exist that must be kept in mind when these data are viewed. The limitations of this analysis include the following: a lack of randomization for the use of spironolactone; a relatively small number of patients who were assigned to spironolactone, which resulted in the studies not being powered to definitely answer the question about a benefit of aldosterone antagonists in ...
There is a lack of evidence that medicines for osteoarthritis are effective in the long term, according to a review in the Journal of the American Medical Association.
Although 6% may not seem like much to the casual observer, 5.7 Mb/d represents the largest oil supply disruption ever, surpassing the combined loss of Kuwaiti and Iraqi production following the latters invasion of the former in August 1990 that drove a doubling of oil prices, seeing the US plun...
Abstract. This paper describes an approach to derive probabilistic predictions of local winter storm damage occurrences from a global medium-range ensemble prediction system (EPS). Predictions of storm damage occurrences are subject to large uncertainty due to meteorological forecast uncertainty (typically addressed by means of ensemble predictions) and uncertainties in modelling weather impacts. The latter uncertainty arises from the fact that local vulnerabilities are not known in sufficient detail to allow for a deterministic prediction of damages, even if the forecasted gust wind speed contains no uncertainty. Thus, to estimate the damage model uncertainty, a statistical model based on logistic regression analysis is employed, relating meteorological analyses to historical damage records. A quantification of the two individual contributions (meteorological and damage model uncertainty) to the total forecast uncertainty is achieved by neglecting individual uncertainty sources and analysing ...
This paper explores ways to integrate model uncertainty into policy evaluation. We first describe a general framework for the incorporation of model uncertainty into standard econometric calculations. This framework employs Bayesian model averaging methods that have begun to appear in a range of economic studies. Second, we illustrate these general ideas in the context of assessment of simple monetary policy rules for some standard New Keynesian specifications. The specifications vary in their treatment of expectations as well as in the dynamics of output and inflation. We conclude that the Taylor rule has good robustness properties, but may reasonably be challenged in overall quality with respect to stabilization by alternative simple rules that also condition on lagged interest rates, even though these rules employ parameters that are set without accounting for model uncertainty. ...
Uncertainty quantification (UQ) is the science of quantitative characterization and reduction of uncertainties in both computational and real world applications. It tries to determine how likely certain outcomes are if some aspects of the system are not exactly known. An example would be to predict the acceleration of a human body in a head-on crash with another car: even if we exactly knew the speed, small differences in the manufacturing of individual cars, how tightly every bolt has been tightened, etc., will lead to different results that can only be predicted in a statistical sense. Many problems in the natural sciences and engineering are also rife with sources of uncertainty. Computer experiments on computer simulations are the most common approach to study problems in uncertainty quantification. Uncertainty can enter mathematical models and experimental measurements in various contexts. One way to categorize the sources of uncertainty is to consider: Parameter uncertainty This comes from ...
Description: The purpose of this dissertation is to develop a theory that helps explain the conditions under which firms select certain project evaluation techniques. This study uses contingency theory to analyze the impact of environmental uncertainty on the choice of project evaluation techniques. In addition to a direct measure of uncertainty, several dimensions of uncertainty are included in this study. These dimensions of uncertainty include control structure, method of financing, foreign assets, method of growth, and product domination. This study also analyzes the use of project evaluation, management science and risk management techniques in US firms over time and in UK firms over time in order to compare to prior research. A comparison of firms in the two countries are also provided. The primary method of data collection was a survey instrument. Data were also collected from annual reports and various other public sources. The variables that appear significant in the choice of project ...
Description: The purpose of this dissertation is to develop a theory that helps explain the conditions under which firms select certain project evaluation techniques. This study uses contingency theory to analyze the impact of environmental uncertainty on the choice of project evaluation techniques. In addition to a direct measure of uncertainty, several dimensions of uncertainty are included in this study. These dimensions of uncertainty include control structure, method of financing, foreign assets, method of growth, and product domination. This study also analyzes the use of project evaluation, management science and risk management techniques in US firms over time and in UK firms over time in order to compare to prior research. A comparison of firms in the two countries are also provided. The primary method of data collection was a survey instrument. Data were also collected from annual reports and various other public sources. The variables that appear significant in the choice of project ...
Ive been looking at it from a different perspective. From the fitted equation for y, we can calculate dy/dt. The question is, what is the uncertainty on this calculated velocity dy/dt? According to the OP, the root mean square error on y (interpreted by me to be the uncertainty on y) is u_y. My focus was on getting an estimate of the rms error on the velocity dy/dt, which Im interpreting as the uncertainty on dy/dt. My method of doing this is by estimating the local deviation between the fitted velocity, and the velocity that would be obtained by differentiating the displacement data with respect to time. Assuming that the deviations in the displacements at the various times are uncorrelated with each other, I came up with the result that u_v=√2u_y/Δt ...
Managing Uncertainties in Interactive Systems: 10.4018/978-1-59904-849-9.ch153: To adapt users input and tasks an interactive system must be able to establish a set of assumptions about users profiles and task characteristics, which is
In this episode of the Managing Uncertainty Podcast, the experts at Bryghtpath discuss Physical Security Penetration Testing, aka Red Teaming
Certain feedingstuffs are sources of contamination for animals with cadmium (Cd) and lead (Pb). Different approaches for sample digestion, performance assessment, and measurement uncertainty for the...
This book presents worked examples of five analytical procedures. These practical examples address traceability, validation and measurement uncertainty aspects in a systematic and consistent way, and cover applications in the analysis of water, food, as well as ores and minerals. This concept is bas.... More. ...
Natural night ventilation is an energy efficient way to improve thermal summer comfort. Coupled thermal and ventilation simulation tools predict the performances. Nevertheless, the reliability of the simulation results with regard to the assumptions in the input, is still unclear. Uncertainty analysis is chosen to determine the uncertainty on the predicted performances of
Told in three parts, the book explores associations between economic growth, policy uncertainty and the key domestic and international transmission channels, and transmission effects, of global financial regulatory and domestic macro-economic uncertainties on subdued and volatile economic recovery, financial channels, lending rate margins, and credit growth. This short report describes the PASTRES (Pastoralism, Uncertainty and Resilience: Global Lessons from the Margins) project, its objectives and early implementation. Resources. The global economic conditions remain fragile and it is difficult to predict customer demand and raw material costs. With new sources of uncertainty seemingly proliferating by the day, a broad economic slowdown should come as no surprise. And as long as the rules and institutions governing the global economy remain in doubt, continued underperformance is to be expected. The World Economic Situation and Prospects Monthly Briefing is prepared by the Global Economic ...
The problem of non-contact surface defect area measurement at complex-shape objects under videoendoscopic control is considered. Major factors contributing to the measurement uncertainty are analyzed for the first time. The proposed method of accuracy analysis is based on the evaluation of 3D coordinates of surface points from 2D projections under assumption of projective camera model and Mahalanobis distance minimization in the image plane. Expressions for area measurement error caused by sum-of-triangles approximation are obtained analytically for practically important cases of cylindrical and spherical surfaces. It is shown that the magnitude of this error component for a single triangle does not exceed 1% for the real values of parameters of the endoscopic imaging system. Expressions are derived for area measurement uncertainty evaluation on arbitrary shape surfaces, caused by measurement errors of 3D coordinates of individual points with and without a priori information about surface shape.
This recommended practice defines a common viewpoint of the evaluation of uncertainty in calibration and its application in testing procedures for Instrument Transformers (ITs). Definition of how to take into account the sources of uncertainty of the measurement system and how to combine their effects in order to evaluate the uncertainty on the measurement results. The recommended practice also presents the common requirements to be used during tests for assessing the accuracy of ITs.
Downloadable! In this paper stochastic dynamic programming is used to investigate land conversion decisions taken by a multitude of landholders under uncertainty about the value of environmental services and irreversible development. We study land conversion under competition on the market for agricultural products when voluntary and mandatory measures are combined by the Government to induce adequate participation in a conservation plan. We study the impact of uncertainty on the optimal conversion policy and discuss conversion dynamics under different policy scenarios on the basis of the relative long-run expected rate of deforestation. Interestingly, we show that uncertainty, even if it induces conversion postponement in the short-run, increases the average rate of deforestation and reduces expected time for total conversion in the long run. Finally, we illustrate our findings through some numerical simulations.
Squeezing what hasnt been squeezed before. Most people attempt to reduce the little uncertainties of life by carrying umbrellas on cloudy days, purchasing automobile insurance or hiring inspectors to evaluate homes they might consider purchasing. For scientists, reducing uncertainty is a no less important goal, though in the weird realm of quantum physics, the term has a more specific meaning.. For scientists working in quantum physics, the Heisenberg Uncertainty Principle says that measurements of properties such as the momentum of an object and its exact position cannot be simultaneously specified with arbitrary accuracy. As a result, there must be some uncertainty in either the exact position of the object, or its exact momentum. The amount of uncertainty can be determined, and is often represented graphically by a circle showing the area within which the measurement actually lies.. Over the past few decades, scientists have learned to cheat a bit on the Uncertainty Principle through a ...
Decision Support Tools & Uncertainty Analysis Services by E Risk Sciences, LLP. Making environmental and public policy decisions involves identifying, ...
Simulations and pre-experiment uncertainty analyses for a hydrogen diffusion experiment using a two side purged membrane ...
TY - JOUR. T1 - Uncertainty analysis for the determination of permeability and specific storage from the pulse-transient technique. AU - Song, Insun. AU - Rathbun, Andrew P.. AU - Saffer, Demian M.. N1 - Funding Information: This work was supported by the Basic Research Program of KIGAM , and by NSF grant EAR-0746192 . We are thankful to Stefan Finsterle at LBNL for his pre-review of this paper, and to two anonymous IJRMMS reviewers for their comments and suggestions.. PY - 2013/12. Y1 - 2013/12. UR - http://www.scopus.com/inward/record.url?scp=84884344208&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=84884344208&partnerID=8YFLogxK. U2 - 10.1016/j.ijrmms.2013.08.032. DO - 10.1016/j.ijrmms.2013.08.032. M3 - Article. AN - SCOPUS:84884344208. VL - 64. SP - 105. EP - 111. JO - International Journal of Rock Mechanics and Mining Sciences. JF - International Journal of Rock Mechanics and Mining Sciences. SN - 1365-1609. ER - ...
Aerosols and their effect on the radiative properties of clouds are one of the largest sources of uncertainty in calculations of the Earths energy budget. Here the sensitivity of aerosol-cloud albedo effect forcing to 31 aerosol parameters is quantified. Sensitivities are compared over three periods; 1850-2008, 1978-2008, and 1998-2008. Despite declining global anthropogenic SO2 emissions during 1978-2008, a cancelation of regional positive and negative forcings leads to a near-zero global mean cloud albedo effect forcing. In contrast to existing negative estimates, our results suggest that the aerosol-cloud albedo effect was likely positive (0.006 to 0.028Wm-2) in the recent decade, making it harder to explain the temperature hiatus as a forced response. Proportional contributions to forcing variance from aerosol processes and natural and anthropogenic emissions are found to be period dependent. To better constrain forcing estimates, the processes that dominate uncertainty on the timescale of ...
How do changes in employment uncertainty matter for fertility? Empirical studies on the impact of employment uncertainty on reproductive decision-making offer a variety of conclusions, ranging from ge
Biomechanical dynamics simulations facilitate the investigation of fundamental principles and concepts in human motions. The simulation results help to explain experimentally observed phenomena and reveal underlying mechanisms. Due to unavoidable restrictions in biomechanical measurements and the determination of personalized model parameters, the simulation results always lie within a specific range of possible solutions. Since these uncertainties can have a significant influence on derived scientific conclusions and clinical decisions, this thesis provides a systematic uncertainty and sensitivity analysis of the common inverse dynamics simulation to assess uncertainty propagation and the contribution of individual uncertainty sources in the estimation of joint torques resulting from particular human motions. The analysis evaluates uncertainties and sensitivities in selected joint torque estimates of the lower limbs for three motion tasks performed by a female and male subject. It follows the ...
During a nuclear plant accident, five accident events are usually considered, including core uncovery, core outlet temperature arrived at 650 °C, core support plate failure, reactor vessel failure and containment failure. In accident emergency aspect, when an accident happens, the initial event can be utilized in the severe accident management system which is based on MAAP to simulate the long process of the accident, so as to provide support for operators to take actions. However, in MAAP, many sensitivity parameters exist, which reflect phenomenological uncertainty or models uncertainty and will influence the happening time of the five accident events above. In this paper, based on MAAP5 and LOCAs, the CPR1000 is simulated to analyze the influences of MAAP5s sensitivity parameters reflecting phenomenological uncertainty on the accident process, which is aimed to find out the sensitivity parameters associated to the five important accident events and build the database between these ...
Decisions involving uncertainty and risk are standard occurrences in water resource management. Demand/sales models need information about future population, economic cycles, rates, passive conservation, and weather, all of which can be uncertain. Decisions about the timing and size of capital investments, built on inaccurate estimates of future levels of demand and supply, can therefore be flawed. Similarly, uncertainty about future sales confounds financial planning. Because information about uncertainty and risk is seldom expressed in concrete terms, ambiguity abounds. Meanwhile, the effect of uncertainty on decisions tends to be downplayed. Accordingly, an adequate accounting for uncertainty and risk requires not only new analytic approaches, but advances in both the way analysts communicate with policy makers and in the way policy makers communicate with each other. This project presents the principles and methods of the new discipline of probability management to address these issues, providing a
Aim of the study. The aim of the study was to assess the degree of illness uncertainty and to determine the correlates of uncertainty, as well as to analyse relationships between uncertainty and quality of life of patients with multiple sclerosis. Materials and methods. The study sample consisted of 40 patients with MS diagnosis, including 29 women and 11 men aged 23 65 years. Uncertainty was assessed using the Polish version of the Mishel Unc ertainty in Illness Scale (MUIS), quality of life with the help of MSQOL 54 questionnaire, anxiety and depression with the HADS scale, and the neurological status with the EDSS scale ...
Uncertainty often affects molecular biology experiments and data for different reasons. Heterogeneity of gene or protein expression within the same tumor tissue is an example of biological uncertainty which should be taken into account when molecular markers are used in decision making. Tissue Microarray (TMA) experiments allow for large scale profiling of tissue biopsies, investigating protein patterns characterizing specific disease states. TMA studies deal with multiple sampling of the same patient, and therefore with multiple measurements of same protein target, to account for possible biological heterogeneity. The aim of this paper is to provide and validate a classification model taking into consideration the uncertainty associated with measuring replicate samples. We propose an extension of the well-known Naïve Bayes classifier, which accounts for biological heterogeneity in a probabilistic framework, relying on Bayesian hierarchical models. The model, which can be efficiently learned from the
Aerosols affect the climate both directly and indirectly. The direct effect comes from their influence on the radiation balance by scattering and absorption of solar radiation, while the indirect effect is based on the ways in which aerosols interact via clouds. Currently the total anthropogenic aerosol forcing includes one of the main uncertainties in the assessment of human induced climate change. The aerosol direct radiative effect (ADRE) can be simulated with either the radiative transfer modelling or estimated with solar radiation and aerosol amount measurements. Both approaches include significant uncertainties and this thesis focuses on the uncertainties on the measurement based estimation of ADRE and the uncertainties therein. The main scientific objectives of this thesis are to seek answers to the following four questions: 1) are the machine learning algorithms better than the a traditional lookup table (LUT) approach in estimating aerosol load (aerosol optical depth, AOD)?; 2) what is ...
TY - JOUR. T1 - SU‐F‐BRA‐12. T2 - Comprehensive Uncertainty Analysis of Proton Stopping‐Power‐Ratio Estimation Using a KV‐MV Dual Energy CT Scanner (DECT) for Margin Reduction. AU - Yang, M.. AU - Zhu, X.. AU - Clayton, J.. AU - Virshup, G.. AU - Mohan, R.. AU - Dong, L.. PY - 2011. Y1 - 2011. N2 - Purpose: To analyze the uncertainties in proton stopping‐power‐ratios (SPRs) calculation using a kV‐MV DECT and evaluate the potential for margin reduction for proton therapyMethods: Sources of uncertainties in SPR estimation were broken into five categories: CT imaging uncertainties, CT modeling error, uncertainties in the mean‐excitation‐energy, SPR variation with proton energy and uncertainties due to variations in human tissue compositions. Additionally, lung, soft and bone tissues were analyzed separately because their uncertainties are too different to be considered as the same tissue type. The uncertainty of 1‐standard‐deviation (1‐SD) was determined for each ...
This paper presents a methodology to represent and propagate epistemic uncertainties within a scenario-based earthquake risk model. Unlike randomness, epistemic uncertainty stems from incomplete, vague or imprecise information. This source of uncertainties still requires the development of adequate tools in seismic risk analysis. We propose to use the possibility theory to represent three types of epistemic uncertainties, namely imprecision, model uncertainty and vagueness due to qualitative information. For illustration, an earthquake risk assessment for the city of Lourdes (Southern France) using this approach is presented. Once adequately represented, uncertainties are propagated and they result in a family of probabilistic damage curves. The latter is synthesized, using the concept of fuzzy random variables, by means of indicators bounding the true probability to exceed a given damage grade. The gap between the pair of probabilistic indicators reflects the imprecise character of uncertainty related
In intelligent tutoring systems, student or user modeling implies dealing with imperfect and uncertain knowledge. One of the artificial intelligence techniques used for uncertainty management is that of Bayesian networks. This paradigm is recommended in the situation when exist dependencies between data and qualitative information about these data. In this work we present a student knowledge diagnosis model based on representation with Bayesian networks. The educational system incorporate a multimedia interface for accomplishes the testing tools. The results of testing sessions are represented and interpreted with probability theory in order to ensure an adapted support for the student. The aims of the computer assisted application that contains this diagnose module are to support the student in personalized learning process and errors explanation.
As a very fundamental principle in quantum physics, uncertainty principle has been studied intensively via various uncertainty inequalities. A natural and fundamental question is whether an equality exists for the uncertainty principle. Here we derive an entropic uncertainty equality relation for a bipartite system consisting of a quantum system and a coupled quantum memory, based on the information measure introduced by Brukner and Zeilinger (Phys. Rev. Lett. 83:3354, 1999). The equality indicates that the sum of measurement uncertainties over a complete set of mutually unbiased bases on a subsystem is equal to a total, fixed uncertainty determined by the initial bipartite state. For the special case where the system and the memory are the maximally entangled, all of the uncertainties related to each mutually unbiased base measurement are zero, which is substantially different from the uncertainty inequality relation. The results are meaningful for fundamental reasons and give rise to operational
Experiments with relatively high doses are often used to predict risks at appreciably lower doses. A point of departure (PoD) can be calculated as the dose associated with a specified moderate response level that is often in the range of experimental doses considered. A linear extrapolation to lower doses often follows. An alternative to the PoD method is to develop a model that accounts for the model uncertainty in the dose-response relationship and to use this model to estimate the risk at low doses. Two such approaches that account for model uncertainty are model averaging (MA) and semi-parametric methods. We use these methods, along with the PoD approach in the context of a large animal (40,000+ animal) bioassay that exhibited sub-linearity. When models are fit to high dose data and risks at low doses are predicted, the methods that account for model uncertainty produce dose estimates associated with an excess risk that are closer to the observed risk than the PoD linearization. This ...
The current paper presents a comparative investigation of the experimental as well as simulated evaluation of effective area and the associated uncertainties, of a pneumatic pressure reference standard (NPLI-4) of CSIR-National Physical Laboratory, India, (NPLI). The experimental evaluation has been compared to the simulated estimation of the effective area obtained through Monte Carlo method (MCM). The Monte Carlo method has been applied by taking fixed number of trials (FMCM) and also by trials chosen adaptively (AMCM). The measurement uncertainties have been calculated using the conventional method, i.e., law of propagation of uncertainty (LPU) as well as MCM. Experimentally, the NPLI-4 has cross-floated against our newly established pneumatic primary pressure standard (NPLI-P10), which is a large diameter piston gauge. An excellent agreement in effective area and measurement uncertainty has been observed between these approaches ...
TY - JOUR. T1 - Identification and uncertainty estimation of vertical reflectivity profiles using a Lagrangian approach to support quantitative precipitation measurements by weather radar. AU - Hazenberg, P.. AU - Torfs, P. J.J.F.. AU - Leijnse, H.. AU - Delrieu, G.. AU - Uijlenhoet, R.. PY - 2013/9/27. Y1 - 2013/9/27. N2 - This paper presents a novel approach to estimate the vertical profile of reflectivity (VPR) from volumetric weather radar data using both a traditional Eulerian as well as a newly proposed Lagrangian implementation. For this latter implementation, the recently developed Rotational Carpenter Square Cluster Algorithm (RoCaSCA) is used to delineate precipitation regions at different reflectivity levels. A piecewise linear VPR is estimated for either stratiform or neither stratiform/convective precipitation. As a second aspect of this paper, a novel approach is presented which is able to account for the impact of VPR uncertainty on the estimated radar rainfall variability. ...
Large uncertainties may exist in modeling various processes determining fisheries population dynamics. The uncertainties may come from various sources such as environmental variations (process errors), measurement errors, and model errors. In order to quantify the uncertainties, an understanding of the complex model error structure in the population dynamic models and how the model error structure affects the parameter estimation is important. In this study I evaluated and quantified the uncertainties in modeling various processes of fisheries population dynamics using Monte Carlo simulations and applied the proposed methods to Atlantic cod stocks. -- The generalized linear model approach, which can readily deal with different error structures, were used to identify suitable model error structure in stock-recruitment modeling, stock biomass modeling, and age-structure population modeling. A simulation study was developed to evaluate the influence of stock mixing on the collection of fish growth ...
This paper deals with the robust performance problem of a linear time-invariant control system in the presence of robust controller uncertainty. Assuming that plant uncertainty is modeled as an additive perturbation, a geometrical approach is followed in order to find a necessary and sufficient condition for robust performance in the form of a bound on the magnitude of controller uncertainty. This frequency domain bound is derived by converting the problem into an optimization problem, whose solution is shown to be more time-efficient than a conventional structured singular value calculation. The bound on controller uncertainty can be used in controller order reduction and implementation problems.
Hashimoto, Shintaro; Sato, Tatsuhiko. Particle transport simulations based on the Monte Carlo method have been applied to shielding calculations. Estimation of not only statistical uncertainty related to the number of trials but also systematic one induced by unclear physical quantities is required to confirm the reliability of calculated results. In this study, we applied a method based on analysis of variance to shielding calculations. We proposed random- and three-condition methods. The first one determines randomly the value of the unclear quantity, while the second one uses only three values: the default value, upper and lower limits. The systematic uncertainty can be estimated adequately by the random-condition method, though it needs the large computational cost. The three-condition method can provide almost the same estimate as the random-condition method when the effect of the variation is monotonic. We found criterion to confirm convergence of the systematic uncertainty as the number ...
Managing an invasive species is particularly challenging as little is generally known about the species biological characteristics in its new habitat. In practice, removal of individuals often starts before the species is studied to provide the information that will later improve control. Therefore, the locations and the amount of control have to be determined in the face of great uncertainty about the species characteristics and with a limited amount of resources. We propose framing spatial control as a linear programming optimization problem. This formulation, paired with a discrete reaction-diffusion model, permits calculation of an optimal control strategy that minimizes the remaining number of invaders for a fixed cost or that minimizes the control cost for containment or protecting specific areas from invasion. We propose computing the optimal strategy for a range of possible model parameters, representing current uncertainty on the possible invasion scenarios. Then, a best strategy can be
The Indian Ocean Tuna Commission (IOTC),. RECOGNISING the authority and responsibility of IOTC to manage bigeye tuna in the IOTC area of competence (Convention Area), at the international level;. RECOGNISING ALSO the nature of the international market for bigeye tuna in the Convention Area;. RECOGNISING ALSO that there is uncertainty on the catch of bigeye tuna in the Convention Area and that the availability of trade data would greatly assist in reducing such uncertainty;. RECOGNISING ALSO that bigeye tuna is the main target species of flag of convenience fishing operations and that most of the bigeye tuna harvested by such fishing vessels are exported to Contracting Parties, especially to Japan;. RECALLING that the International Commission for the Conservation of Atlantic Tunas (ICCAT) has established its Bluefin Tuna, Bigeye Tuna and Swordfish Statistical Document Programs, and that the Commission for the Conservation of Southern Bluefin Tuna (CCSBT) has also established its Southern ...
Archaeozoological and genetic data indicate that taurine cattle were first domesticated from local wild ox (aurochs) in the Near East some 10,500 years ago. However, while modern mitochondrial DNA variation indicates early Holocene founding event(s), a lack of ancient DNA data from the region of origin, variation in mutation rate estimates and limited application of appropriate inference methodologies have resulted in uncertainty on the number of animals first domesticated. A large number would be expected if cattle domestication was a technologically straightforward and unexacting region-wide phenomenon, while a smaller number would be consistent with a more complex and challenging process. We report mitochondrial DNA sequences from 15 Neolithic to Iron Age Iranian domestic cattle and, in conjunction with modern data, use serial coalescent simulation and approximate Bayesian computation to estimate that around 80 female aurochs were initially domesticated. Such a low number is consistent with ...
Introduction. A key issue in understanding the nitrogen (N) cycle is to determine human-induced perturbations to the natural N cycle. Such determination involves first understanding, describing, and quantifying the natural N cycle at global, regional, and local scales. The concentration of N species in the environment varies greatly over short distances. This natural variability can make it difficult to evaluate human influences on the N cycle. Ideally, all the components of the natural N cycle should be measured with known precision and accuracy. In practice, this is impossible. In reality, estimates are made of the magnitude of the major components of the N cycle based on fragmentary measurements. There are large uncertainties on the magnitude of the estimated natural fluxes of N and the natural storage of N in the N reservoirs. For example, the estimates of marine N fixation range from 40-200 million metric tons/yr, atmospheric deposition of organic-N 10-100 million metric tons/yr and, ...
There is often uncertainty on how validation and verification of newly introduced tests should be conducted, and there is a real risk of verification becoming a meaningless ritual, rather than a useful exercise. This article reviews the literature and makes recommendations regarding the validation and verification of automated urine particles analysers. A generic practical approach to verification is also recommended. For many analysers, the accuracy of white blood cells, epithelial cells and bacterial counts is corroborated by a number of independent evaluations; thus, any verification laboratory work could be significantly scaled down. Conversely, in the scenario that automated urine microscopy is used as a screening test to reduce the number of urines cultured, the extremely variable performance reported in the literature requires a full-scale verification to define the optimal cut-off values that give a sensitivity of ,98% with the local settings and circumstances. With some analysers, the ...
Although coronary-artery bypass grafting (CABG) is the standard choice of revascularization for significant left main coronary artery (LMCA) disease, percutaneous coronary intervention (PCI) for LMCA disease has been widely expanded with adoption of drug-eluting stents (DES). Several small- and moderate-sized trials of CABG and first-generation DES showed that PCI might be a good alternative for selected patients with LMCA disease. However, these early trials were relatively underpowered and comparative results of contemporary DES and CABG were clearly required. Subsequently, two large-sized trials comparing CABG and contemporary DES (EXCEL and NOBLE) were conducted, but these trials showed conflicting results with regards to the effects of PCI and CABG on clinical outcomes, which raises further uncertainty on the optimal revascularization for LMCA disease. This article serves to summarize the key findings of landmark clinical trials, to share our knowledge and experience and to express personal
The optimization of the coated metallic nanoparticles and nanoshells is a current challenge for biological applications, especially for cancer photothermal therapy, considering both the continuous improvement of their fabrication and the increasing requirement of efficiency. The efficiency of the coupling between illumination with such nanostructures for burning purposes depends unevenly on their geometrical parameters (radius, thickness of the shell) and material parameters (permittivities which depend on the illumination wavelength). Through a Monte-Carlo method, we propose a numerical study of such nanodevice, to evaluate tolerances (or uncertainty) on these parameters, given a threshold of efficiency, to facilitate the design of nanoparticles. The results could help to focus on the relevant parameters of the engineering process for which the absorbed energy is the most dependant. The Monte-Carlo method confirms that the best burning efficiency are obtained for hollow nanospheres and exhibit ...
Downloadable! Herd behavior is often viewed as a signi cant threat for the stability and eciency of nancial markets. This paper sheds new light on the relevance of herd behavior for observed correlation of trades. We introduce numerical simulations of a herd model to derive theory-guided predictions regarding the impact of various aspects of uncertainty on herding intensity. We test the predictions using a novel data set including all real-time transactions of institutional investors in the German stock market. In light of the model simulations, empirical results strongly suggest that the observed correlation of trades is mainly due to the common reaction of investors to new public information and should not be misinterpreted as herd behavior.
Increasing attention has been paid food as a cause of IBS. Food ingestion precipitates or exacerbates symptoms, such as abdominal pain and bloating in patients with IBS through different hypothesised mechanisms including immune and mast cell activation, mechanoreceptor stimulation and chemosensory activation.. Wheat is one of the most relevant IBS triggers, although which component(s) of this cereal is/are involved remain(s) unknown. Gluten, other wheat proteins, for example, amylase-trypsin inhibitors, and fructans (the latter belonging to fermentable oligo-di-mono-saccharides and polyols (FODMAPs)), have been identified as possible factors for symptom generation/exacerbation.. This uncertainty on the true culprit(s) opened a scenario of semantic definitions favoured by the discordant results of double-blind placebo-controlled trials, which have generated various terms ranging from non-coeliac gluten sensitivity to the broader one of non-coeliac wheat or wheat protein sensitivity or, even, ...
To the Editor:. Chronic cough is a difficult clinical problem, partly because there is an absence of well-validated means to assess cough [1, 2]. We have previously reported that the semi-automated computerised Leicester Cough Monitor detects cough accurately over 6 h and that cough frequency is increased in patients with chronic cough compared to controls [3, 4]. There remains uncertainty on the performance of the system over 24 h and across the range of expected cough frequency in larger populations. We set out to address these questions in healthy adult volunteers and adult volunteers with respiratory disease.. 44 healthy volunteers were recruited from those responding to a poster advertisement. All reported no current respiratory symptoms, were nonsmokers with a ,5 pack-yr past smoking history and had normal spirometric values, methacholine airway responsiveness and induced sputum inflammatory cell counts. 78 patients with respiratory disease were recruited from respiratory clinics. The ...
Context: Many different rehabilitation exercises have been recommended in the literature to target the gluteus medius (GMed) muscle based mainly on single-electrode, surface electromyography (EMG) measures. With the GMed consisting of 3 structurally and functionally independent segments, there is uncertainty on whether these exercises will target the individual segments effectively. Objective: To measure individual GMed segmental activity during 6 common, lower-limb rehabilitation exercises in healthy young adults, and determine if there are significant differences between the exercises for each segment. Method: With fine-wire EMG electrodes inserted into the anterior, middle, and posterior segments of the GMed muscle, 10 healthy young adults performed 6 common, lower-limb rehabilitation exercises. Main Outcome Measures: Recorded EMG activity was normalized, then reported and compared with median activity for each of the GMed segments across the 6 exercises. Results: For the anterior GMed ...
Several Western European countries are planning for a massive offshore renewable energy (i.e. wind and wave energy) development (ORED) along the European Atlantic coast and in the Baltic Sea. Acknowledging the scale of ORED, there is an increasing interest in the opportunities offered by the fishery closures and the addition of artificial hard substrata. This is in tandem with uncertainties on positive and negative effects on benthic assemblages and specific species of this large-scale deployment of artificial reefs.. This thesis focuses on the artificial reef effects of ORED, dealing with benthic assemblages on and in the vicinity of wind- and wave power foundations. Field surveys within offshore wind- and wave farms as well as targeted field experiments were conducted. Results suggest that wind- and wave power foundations can positively affect local abundances and diversity of several species of fish and decapods. Reef profile up to 1 m above the seabed may enhance benthic fish numbers. ...
Sigma-Aldrich Corp.s SIAL first-quarter earnings rose 4.3% as the chemical company was helped by improving sales to diagnostic and testing laboratories.. The company, which supplies chemical products and kits for high-technology scientific research, has seen its sales strengthen in recent quarters, helped by acquisitions. Sigma-Aldrich has also been spending to increase growth in China, India and Brazil. However, uncertainty on the economy and research funding in the U.S. and Europe has made some customers cautious about spending.. Chief Executive Rakesh Sachdev said Thursday that overall end markets remain steady with improving pharma trends offset by slower academic spending.. Sigma-Aldrich reported a profit of $122 million, or $1.01 a share, up from $117 million, or 96 cents a share, a year earlier. The latest period included a two-cent negative impact from currency exchange rates. Revenue increased 1.5% to $675 million. Organic sales--which typically include foreign-exchange, acquisition ...
National Grid has taken another step to reduce the coronavirus financial strain and economic uncertainty on upstate New York customers by deferring a bill increase that was scheduled to take effect April 1. The company has asked New York regulators for permission to postpone the previously approved gas and electricity delivery price increases in recognition of the unprecedented hardships the COVID-19 outbreak continues to bring to families across the region.
TY - JOUR. T1 - Elucidation of the mechanism behind the influences of uncertainty avoidance on customer attitudes towards Japanese products and services. AU - Frank, Björn. AU - Torrico, Boris Herbas. AU - Enkawa, Takao. PY - 2013/9/27. Y1 - 2013/9/27. N2 - Sparked by accelerating globalization, many studies have examined the influences of Hofstedes cultural scores on consumer attitudes. Past research suggested that high uncertainty avoidance, a characteristic of Japanese culture, leads to strict customer evaluations and low customer satisfaction. While researchers found clear evidence of this effect for uncertainty avoidance as a facet of country culture, they found mixed evidence for uncertainty avoidance as a personal cultural trait. Based on consumer data from ten industries in Japan, this article thus explores the mechanism linking personal uncertainty avoidance to customer satisfaction and its antecedents (perceived quality, perceived value and firm image). The results suggest that ...
TY - JOUR. T1 - Automatic web service composition based on uncertainty execution effects. AU - Wang, Pengwei. AU - Ding, Zhijun. AU - Jiang, Changjun. AU - Zhou, Mengchu. AU - Zheng, Yuwei. N1 - Publisher Copyright: © 2008-2012 IEEE.. PY - 2016/7/1. Y1 - 2016/7/1. N2 - By arranging multiple existing web services into workflows to create value-added services, automatic web service composition has received much attention in service-oriented computing. A large number of methods have been proposed for it although most of them are merely based on the matching of input-output parameters of services. Besides these parameters, some other elements can affect the execution of services and their composition, such as the preconditions and service execution results. In particular, the execution effects of some services are often uncertain because of the complex and dynamically changing application environments in the real world, and this can cause the emergence of nondeterministic choices in the workflows ...
In this qualitative study of outpatients and their physicians at a public hospital in Sri Lanka, antibiotic prescriptions for ARTIs were common (70%). Interestingly, there was a disassociation between patients expectations for antibiotics and physicians perceptions of patient expectations. Patients generally had a low level of knowledge regarding ARTI etiology and antibiotics, with the main expectation for treatment being the receipt of a medication prescription. Physicians incorrectly perceived that patients desired antibiotics, and also cited factors such as diagnostic uncertainty, competition with the private sector, and lack of time as reasons for possible antibiotic over-prescription. Patients were generally satisfied with treatment received in the OPD, but physicians identified both systematic and patient-based factors that they felt hindered the optimal delivery of care for ARTIs.. Patients desire for antibiotics was the most common reason listed by physicians for possible antibiotic ...
Constrained partitioning of autotrophic and heterotrophic respiration reduces model uncertainties of forest ecosystem carbon fluxes but not stocks Academic Article ...
IBC is a poorly understood disease with a dismal prognosis. Diagnosis is based on variously appreciated clinical signs, and prognostic factors are sorely needed. Despite multimodality treatments, the overall outcome of IBC is almost as grim as that of metastatic breast cancer [25, 26]. Identification of a molecular signature might help to improve the diagnosis, as well as the prognostication and targeted therapy of IBC. The specific molecular alterations underlying IBC are largely unknown, owing to the rarity of the disease together with diagnostic uncertainties and the small size of diagnostic samples, which may have hindered past molecular studies. Moreover, previous molecular studies often grouped IBCs together with non inflammatory LABCs, whereas IBC was recently shown to be distinct from other forms of LABC, probably with different underlying molecular alterations [27, 28].. Two major lines of evidence implicate NF-κB-associated pathways in IBC. First, NF-κB target genes are involved in ...
The use of coronary angiography to investigate patients at risk of coronary artery narrowings has become universal. In most cases, this investigation leads to a successful treatment plan with revascularisation recommended where appropriate. However in a substantial number of patients, the images taken of the coronary arteries can lead to diagnostic uncertainty. Increasingly, doctors are using devices called pressure wires to clarify the significance of coronary artery narrowings in order to tailor patient treatment on an individual basis.. The Radi pressure wire is well recognised as a reliable tool in assessing whether a narrowing is significant in functional terms, that is, does it significantly restrict blood flow to the heart muscle.It consists of a fine wire that is fed into individual major coronary arteries to measure pressure within the vessel itself. In conjunction with the images taken of the arteries, it is very useful in deciding how best to treat patients.. This study enrolls ...
We invite you to discover ThyroidPrint, the most accurate genomic test ever developed for indeterminate thyroid cytology. ThyroidPrint solves the diagnostic uncertainty for patients with Indeterminate thyroid nodules avoiding up to 88% of unnecessary surgeries ...
Recently, time-lapse seismic (4D seismic) has been steadily used to demonstrate the relation between field depletion and 4D seismic response, and, subsequently, to provide more efficient field management. A key component of reservoir monitoring is the knowledge of fluid movement and pressure variation. This information is vital in assisting infill drilling and as a reliable source of data to update reservoir models, and, consequently, in helping to improve model-based reservoir management and decision-making processes. However, in practice, varying levels of uncertainty are inherent in the 4D seismic interpretation of reservoirs that uses a multipart production regime. The complex nature of some 4D seismic signals emphasizes the role of the competing effects of geology, rock and fluid interactions. Hence, a reliable 4D interpretation requires an interdisciplinary approach that entails data analysis and insights from geophysics, engineering and geology. In this study, a stepwise workflow was ...
An introduction to analysis and design of feedback control systems, including classical control theory in the time and frequency domain. Modeling of physical, biological, and information systems using linear and nonlinear differential equations. Linear vs. nonlinear models, and local vs. global behavior, Input/ output response, modeling and model reduction, Stability and perfor¬mance of interconnected systems, including use of block diagrams, Bode plots, the Nyquist criterion, and Lyapunov functions. Robustness and uncertainty management in feedback systems through stochastic and deterministic methods. Basic principles of feedback and its use as a tool for altering the dynamics of systems and managing uncertainty methods. Introductory random processes, Kalman filtering, norms of signals and systems. Topics in 221B: The aim of this course is to introduce the student to the area of nonlinear control systems with a focus on systems analysis and control design. Nonlinear phenomena including ...
The uncertainty is on rise as most of the economy are deciding to become close economy which will affect the global trade. Low crude oil price is going to affect the economies of the major oil supplier (OPEC). The economy was yet to get out of the global financial crisis but this COVID-19 will add more lag in the economy. ...
Background: Young adults with congenital heart disease (CHD) are at risk for chronic illness uncertainty in 4 domains: ambiguity about the state of their illness; lack of information about the disease, its treatment, and comorbidities; complexity of the healthcare system and relationship with healthcare providers; and unpredictability of the illness course and outcome. Chronic uncertainty has been associated with posttraumatic stress symptoms (PTSS) and posttraumatic stress disorder (PTSD). Objective: The aims of this study were to explore how young adults with CHD experience uncertainty and to describe the relationship between PTSS and the appraisal and management process. Methods: An exploratory, mixed methods design was used. Data were collected in person and via Skype from 25 participants (19-35 years old), who were diagnosed with CHD during childhood and able to read and write English. In-depth interviews and the University of California at Los Angeles Posttraumatic Stress Disorder Reaction ...
The majority of existing studies for quantifying uncertainties in climate change impact assessments suggest only the uncertainties of each stage, and not the total uncertainty and its propagation in the whole procedure. Therefore, this study has proposed a new method, the Uncertainty Delta Method (UDM), which can quantify uncertainties using the variances of projections (as the UDM is derived from the first-order Taylor series expansion), to allow for a comprehensive quantification of uncertainty at each stage and also to provide the levels of uncertainty propagation, as follows: total uncertainty, the level of uncertainty increase at each stage, and the percentage of uncertainty at each stage. For quantifying uncertainties at each stage as well as the total uncertainty, all the stages - two emission scenarios (ES), three Global Climate Models (GCMs), two downscaling techniques, and two hydrological models - of the climate change assessment for water resources are conducted. The total ...
In the event of a new infectious disease outbreak, mathematical and simulation models are commonly used to inform policy by evaluating which control strategies will minimize the impact of the epidemic. In the early stages of such outbreaks, substantial parameter uncertainty may limit the ability of models to provide accurate predictions, and policymakers do not have the luxury of waiting for data to alleviate this state of uncertainty. For policymakers, however, it is the selection of the optimal control intervention in the face of uncertainty, rather than accuracy of model predictions, that is the measure of success that counts. We simulate the process of real-time decision-making by fitting an epidemic model to observed, spatially-explicit, infection data at weekly intervals throughout two historical outbreaks of foot-and-mouth disease, UK in 2001 and Miyazaki, Japan in 2010, and compare forward simulations of the impact of switching to an alternative control intervention at the...
A major challenge in modern robotics is to liberate robots from controlled industrial settings, and allow them to interact with humans and changing environments in the real world. The current research attempts to determine if a neurophysiologically motivated model of cortical function in the primate can help to address this challenge. Primates are endowed with cognitive systems that allow them to maximize the feedback from their environment by learning the values of actions in diverse situations and by adjusting their behavioral parameters (i.e. cognitive control) to accommodate unexpected events. In such contexts uncertainty can arise from at least two distinct sources - expected uncertainty resulting from noise during sensory-motor interaction in a known context, and unexpected uncertainty resulting from the changing probabilistic structure of the environment. However, it is not clear how neurophysiological mechanisms of reinforcement learning and cognitive control integrate in the brain to produce
Author Summary Dengue is one of the most important insect-vectored human viral diseases. The principal vector is Aedes aegypti, a mosquito that lives in close association with humans. Currently, there is no effective vaccine available and the only means for limiting dengue outbreaks is vector control. To help design vector control strategies, spatial models of Ae. aegypti population dynamics have been developed. However, the usefulness of such models depends on the reliability of their predictions, which can be affected by different sources of uncertainty including uncertainty in the model parameter estimation, uncertainty in the model structure, measurement errors in the data fed into the model, individual variability, and stochasticity in the environment. This study quantifies uncertainties in the mosquito population dynamics predicted by Skeeter Buster, a spatial model of Ae. aegypti, for the city of Iquitos, Peru. The uncertainty quantification should enable us to better understand the reliability
The uncertainties of life are manifest every day. Some uncertainties are harder than others. My sister has Stage IV lung cancer. But her future is still uncertain, its quite possible the chemo will kill her long before the cancer can. Shes been in the hospital for two weeks now as a mold has developed in her lungs, thanks to chemo bringing her white blood cell count down to zero. On Thursday, I learned she has developed VRE, a anti-biotic resistant bacteria similar but much more rare than MRSA, the OMG of countless House episodes. Of course, because when you are going to ER three times a day for 90 minute infusions of antibiotics, you develop anti-biotic resistant bacteria. I think it is time for her to eat a lot of dessert. Ice cream, apple pie, chocolate cake, brownies and coffee nips. Go for it ...
During the presurgical evaluation of medically intractable epilepsy, isotopic functional imagery provides an increasing amount of data concerning the potential location of the focus. The aim of this study is to facilitate the surgical decision by presenting an image fusion method able to extract epileptogenic foci from periictal single photon emission computed tomography (SPECT), interictal SPECT, fluoro-desoxy-glucose (FDG) position emission tomography (PET), and flumazenil PET. After spatial coregistration, the images are converted into fuzzy maps whose membership functions indicate the pathological degree of each voxel, according to each modality. These maps are then fused together thanks to a combination operator managing uncertainty (due to the sensitivity) and imprecision (due to poor resolution and partial volume effect) of the images. In the framework of possibilistic theory, this operator mimics the way the physicians evaluate and compare the various exams. The technique was s
My research focuses on attempting to better model when and how actions can alter the uncertainty that the agent confronts, subsequently affecting the perception of risk involved in decisions. I am particularly interested in integrating precepts of causal reasoning with (pragmatic) decision support systems and developing a conception of risk based on the control an agent can exercise over the future states of the world. The motivation for my research stems from the fact that current models of decision making do not resonate with the managerial attitude toward uncertainty, which is viewed as something that they believe they control/influence and may decide to voluntarily engage with it. The endeavour of the research is to preserve the primacy of this intuition in the formal construct of models and produce potentially useful research that could help bridge the gap in the understanding between theorists and practitioners. To add or modify information on this page, please contact us at the following ...
TY - GEN. T1 - Improving identifiability in model calibration using multiple responses. AU - Arendt, Paul D.. AU - Chen, Wei. AU - Apley, Daniel. PY - 2011/12/1. Y1 - 2011/12/1. N2 - The use of complex computer simulations to design, improve, optimize, or simply to better understand complex systems in many fields of science and engineering is now ubiquitous. However, simulation models are never a perfect representation of physical reality. Two general sources of uncertainty that account for the differences between simulations and experiments are parameter uncertainty and model uncertainty. The former derives from unknown model parameters, while the latter is caused by underlying missing physics, numerical approximations, and other inaccuracies of the computer simulation that exist even if all of the parameters are known. To obtain knowledge of these two sources of uncertainty, data from computer simulations (usually abundant) and data from physical experiments (typically more limited) are often ...
Perhaps it would help to choose a more mundane example (I really didnt mean for nuclear war or climate change to become the focus - although they are certainly worthy topics to discuss). A company is considering the launch of a new product - many uncertainties are present. Do we believe that evolutionary processes have prepared the decision makers to assess the risks well?. My answer is that evolution is very unlikely to have worked in this way (no, I cant prove that, but my layman understanding of evolution is that it takes too long to have accomplished what is required). Instead, I believe many of the biases that Kahneman and others have investigated are likely to be relevant in a case like this. Gigerenzers claim that decision makers are sophisticated assessors of risks like this seems unwarranted to me. The exception would be if a decision maker had faced many decisions like this in the past - sort of like Gladwells (Blink) examples where emergency responders act using heuristics - honed ...
The proposed study aims to explore the relationships between perceived uncertainty, hope and adaptation in caregivers of children with Down Syndrome (DS). There are often uncertainties surrounding the prognosis of DS which extend into various aspects of the child s life. In addition to the possibility of chronic medical conditions associated with the syndrome, there is also uncertainty related to the level of independence and cognitive, social and behavioral functioning that the child will achieve. It is not fully understood how caregivers adapt to having a child with DS in light of the uncertainty and the particular challenges associated with this condition. While a high level of perceived uncertainty may be seen as a threat to adaptation, there is also evidence that caregivers may find benefits in uncertainty. Literature suggests that a person s level of hope influences how the perceived uncertainty is appraised and that hope is also related to the process of adaptation. There is no research ...
Bayesian inference is an approach to statistics whereby all forms of uncertainty are described in terms of probability. Bayesian inference applies Bayes theorem to observations in order to infer the probability of the truth of an hypothesis. ...
Reducing the sensitivity of IMPT treatment plans to setup errors and range uncertainties via probabilistic treatment planning. Med Phys. 2009 Jan; 36(1):149-63 ...
Confidence intervals tell you about how well you have determined the mean. Assume that the data really are randomly sampled from a Gaussian distribution. If you do this many times, and calculate a confidence interval of the mean from each sample, youd expect about 95 % of those intervals to include the true value of the population mean. The key point is that the confidence interval tells you about the likely location of the true population parameter.. Prediction intervals tell you where you can expect to see the next data point sampled. Assume that the data really are randomly sampled from a Gaussian distribution. Collect a sample of data and calculate a prediction interval. Then sample one more value from the population. If you do this many times, youd expect that next value to lie within that prediction interval in 95% of the samples.The key point is that the prediction interval tells you about the distribution of values, not the uncertainty in determining the population mean. Prediction ...
Uncertainty in economics is an unknown prospect of gain or loss, whether quantifiable as risk or not. Without it, household ... 11, "Uncertainty and Game Theory" and [end] Glossary of Terms, "Economics of information", "Game theory", and "Regulation" ... 11, "Uncertainty and Game Theory" and [end] Glossary of Terms, "Economics of information", "Game theory", and "Regulation" ... Uncertainty and game theory. Main articles: Information economics, Game theory, and Financial economics ...
Chapter 4: The Uncertainty Principle[edit]. This chapter is about the uncertainty principle. The uncertainty principle says ... The uncertainty principle disproved the idea of a theory that was deterministic, or something that would predict everything in ... A different theory also says that light waves also act like particles; a theory that says this is Heisenberg's uncertainty ... Such a theory must combine the classical theory of gravity with the uncertainty principle found in quantum mechanics. Attempts ...
Intolerance of uncertainty therapy[edit]. Intolerance of uncertainty therapy (IUT) refers to a consistent negative reaction to ... Thus, IUT focuses on helping patients in developing the ability to tolerate, cope with and accept uncertainty in their life in ... Intolerance of uncertainty therapy and motivational interviewing are two new treatments for GAD that are used as either stand- ... recognition of uncertainty, and behavioral exposure. Studies have shown support for the efficacy of this therapy with GAD ...
Uncertainty. Measurements in scientific work are also usually accompanied by estimates of their uncertainty. The uncertainty is ... Uncertainties may also be calculated by consideration of the uncertainties of the individual underlying quantities used. Counts ... of choosing between reciprocally related uncertainties. ... Multiplying together the conjugate pairs of uncertainty limits ... Or counts may represent a sample of desired quantities, with an uncertainty that depends upon the sampling method used and the ...
Uncertainty and risk. Further information: Existential risk from artificial general intelligence. The term "technological ... Discussing the level of uncertainty in AGI estimates, study co-author Stuart Armstrong stated: "my current 80% estimate is ...
Compact relativistic objects and the generalized uncertainty principle[edit]. Based on the generalized uncertainty principle ( ...
Decreasing sensory uncertainty[edit]. It has been widely acknowledged that uncertainty in sensory domains results in an ... they also progressively changed the temporal uncertainty of the auditory cue; eventually concluding that it is the uncertainty ... but it is not until children are eight years or older before they use multiple modalities to reduce sensory uncertainty.[82] ... "Bayesian models: the structure of the world, uncertainty, behavior, and the brain". Annals of the New York Academy of Sciences ...
Uncertainty and risk[edit]. Further information: Existential risk from artificial general intelligence ...
Managing uncertainty[edit]. Print on demand can be used to reduce risk when dealing with "surge" publications that are expected ...
Uncertainty[edit]. This section does not cite any sources. Please help improve this section by adding citations to reliable ...
Scientific uncertainty of full extent of herbicide effects[edit]. The health and environmental effects of many herbicides is ...
GIS uncertainties[edit]. GIS accuracy depends upon source data, and how it is encoded to be data referenced. Land surveyors ... "Modeling the uncertainty of slope and aspect estimates derived from spatial databases" (PDF). Geographical Analysis. 29 (1): ...
An estimate of the uncertainty in the first and second case can be obtained with the binomial probability distribution using ... Predictions of occurrence based on fitted probability distributions are subject to uncertainty, which arises from the following ...
True uncertainty or Knightian uncertainty, which is impossible to estimate or predict statistically (such as the probability of ... Uncertainty perception and risk-taking[edit]. Theorists Frank Knight[104] and Peter Drucker defined entrepreneurship in terms ... Knight, Frank Hyneman (2005). Risk, Uncertainty and Profit. Cosimo, Inc. ISBN 978-1-59605-242-0. .. ... Knight classified three types of uncertainty: *Risk, which is measurable statistically (such as the probability of drawing a ...
Cosmic uncertainty[edit]. Each possibility described so far is based on a very simple form for the dark energy equation of ... Such a description seems to be at odds with everything else in physics, and especially quantum mechanics and its uncertainty ...
Immediately after Heisenberg discovered his uncertainty principle,[17] Bohr noted that the existence of any sort of wave packet ... Modern conceptions and connections to the Heisenberg uncertainty principle[edit]. ... see the Heisenberg uncertainty principle for details of the mechanism). ... implies uncertainty in the wave frequency and wavelength, since a spread of frequencies is needed to create the packet itself.[ ...
Accuracy uncertainties of ,0.01% are required to detect long term solar irradiance variations, because expected changes are in ... Uncertainties of individual observations exceed irradiance variability (∼0.1%). Thus, instrument stability and measurement ... Instrument inaccuracies add a significant uncertainty in determining Earth's energy balance. The energy imbalance has been ... a cryogenic radiometer that maintains the NIST radiant power scale to an uncertainty of 0.02% (1σ). As of 2011 TRF was the only ...
IUPAC 2016, Table 2, 3 combined; uncertainty removed. Harv error: no target: CITEREFIUPAC2016 (help) ...
Causes of uncertainty on Earth[edit]. Famously, the published atomic weight value comes with an uncertainty. This uncertainty ( ... This uncertainty reflects natural variability in isotopic distribution for an element, rather than uncertainty in measurement ( ... The value published can have and uncertainty be an interval like for neon: 20.1797(6), or can be an interval, like for boron: [ ... The "(2)" indicates the uncertainty in the last digit shown, to read 4.002602±0.000002. IUPAC also publishes abridged values, ...
The game of roulette is not subject, in this sense, to uncertainty ... The sense in which I am using the term is that in which ... In economics, this circle of ideas is analysed under the rubric of "Knightian uncertainty". John Maynard Keynes and Frank ... Knight, F. H. (1921) Risk, Uncertainty and Profit ISBN 1-58798-126-2 ...
From the big hole in Earth's ozone layer to over-fishing to the uncertainties of climate change, the world is confronted by ...
uncertainty. *uncertainty and general equilibrium. *uncovered interest parity. *underconsumptionism. *underemployment ...
Uncertainty parameter 0. Observation arc. 87.60 yr (31,997 d). Aphelion. 6.0232 AU. ...
Sociology is the systematic study of society, individuals' relationship to their societies, the consequences of difference, and other aspects of human social action.[31] The meaning of the word comes from the suffix "-logy", which means "study of", derived from Ancient Greek, and the stem "soci-", which is from the Latin word socius, meaning "companion", or society in general. Auguste Comte (1798-1857) coined the term, Sociology, as a way to apply natural science principles and techniques to the social world in 1838.[32][33] Comte endeavoured to unify history, psychology and economics through the descriptive understanding of the social realm. He proposed that social ills could be remedied through sociological positivism, an epistemological approach outlined in The Course in Positive Philosophy [1830-1842] and A General View of Positivism (1844). Though Comte is generally regarded as the "Father of Sociology", the discipline was formally established by another French thinker, Émile Durkheim ...
Uncertainty parameter 2. Observation arc. 10.58 yr (3,864 days). Aphelion. 16.298 AU. ...
Symbolic representations can be used to indicate meaning and can be thought of as a dynamic process. Hence the transfer of the symbolic representation can be viewed as one ascription process whereby knowledge can be transferred. Other forms of communication include observation and imitation, verbal exchange, and audio and video recordings. Philosophers of language and semioticians construct and analyze theories of knowledge transfer or communication. While many would agree that one of the most universal and significant tools for the transfer of knowledge is writing and reading (of many kinds), argument over the usefulness of the written word exists nonetheless, with some scholars skeptical of its impact on societies. In his collection of essays Technopoly, Neil Postman demonstrates the argument against the use of writing through an excerpt from Plato's work Phaedrus (Postman, Neil (1992) Technopoly, Vintage, New York, p. 73). In this excerpt, the scholar Socrates recounts the story of Thamus, ...
"The NIST Reference on Constants, Units, and Uncertainty. NIST. 20 May 2019. Retrieved 2019-05-20.. ... "The NIST Reference on Constants, Units, and Uncertainty. NIST. 20 May 2019. Retrieved 2019-05-20.. ... "The NIST Reference on Constants, Units, and Uncertainty. NIST. 20 May 2019. Retrieved 2019-05-20.. ... "The NIST Reference on Constants, Units, and Uncertainty. NIST. 20 May 2019. Retrieved 2019-05-20.. ...
Distastes or uncertainty?". International Journal of Manpower. 35 (5): 720-744. doi:10.1108/IJM-02-2012-0026. hdl:10419/62444. ...
Teeter, Preston; Sandberg, Jorgen (2016). "Constraining or Enabling Green Capability Development? How Policy Uncertainty ...
Uncertainty parameter 0. Observation arc. 98.72 yr (36059 d). Aphelion. 3.3755 AU (504.97 Gm). ...
... the uncertainty in the computed quantity, σR, is: σ. R. ≈. σ. V. 2. (. 1. I. ). 2. +. σ. I. 2. (. −. V. I. 2. ). 2. =. R. (. σ ... The uncertainty u can be expressed in a number of ways. It may be defined by the absolute error Δx. Uncertainties can also be ... Therefore, our propagated uncertainty is Δ. f. ≈. Δ. x. 1. +. x. 2. ,. {\displaystyle \Delta _{f}\approx {\frac {\Delta _{x}}{1 ... In statistics, propagation of uncertainty (or propagation of error) is the effect of variables uncertainties (or errors, more ...
Hmph!  I just read on the OMB/OIRA website that they have completed their review of Labor Secretary Chaos proposal to change the way that OSHA and MSHA assess workers risk of health hazards. The OIRA website notice says their review was completed on August 25, and it was approved "consistent with change." Well, I guess I didnt really expect Secretary Chao or one of her political associates to call me personally to discuss the August 14 letter that 80 public health scientists sent to her. In that letter, we urged Elaine Chao to withdraw her proposal from OMB review. I… ...
Learn more about Uncertainty Quantification and the activity groups, conferences, journals, and other opportunities that SIAM ... Uncertainty Quantification. This research area covers all aspects of the effects of uncertainty and error on mathematical ... SIAM Conference on Uncertainty Quantification (UQ20). Uncertainty quantification (UQ) is essential for providing informative ... SIAM/ASA Journal on Uncertainty Quantification. Prediction Uncertainties beyond the Range of Experience: A Case Study in ...
Our uncertainty indices for fiscal, monetary, trade and exchange rate policy co-vary positively but also display distinct ... policy matters and uncertainty. Our overall EPU index co-varies positively with implied volatilities for Japanese equities, ... exchange rates and interest rates and with a survey-based measure of political uncertainty. The EPU index rises around ... We develop new economic policy uncertainty (EPU) indices for Japan from January 1987 onwards building on the approach of Baker ...
Uncertainty is part of what they need to know. Greater uncertainty may prompt them to act sooner (to reduce it) or later ( ... Some of that uncertainty concerns facts: What will happen if we make a choice? Some of that uncertainty concerns values: What ... Conveying Uncertainty.. An audit like that in Fig. 2 creates a profile of the uncertainties surrounding scientific results. ... All science has uncertainty. Unless that uncertainty is communicated effectively, decision makers may put too much or too ...
... can be assessed using genetic data, along with other lines of evidence (such as morphological and ...
It is the essence of medical practice to live with uncertainty and to be forced to make decisions on the basis of incomplete ...
Heisenberg Uncertainty Principle of Education. Standardized testing is getting out of control. Too much weight in a school and ...
Uncertainty pressures oil stocks Published: May 20, 2004 at 4:57 p.m. ET By Lisa Sanders. ...
Subprime Uncertainty Fans Out Bears Hedge Funds. Are Basically Worthless;. More Bond Fire Sales. ...
... decision uncertainty), how uncertainty modelling is used in risk assessment, and differ… ... Learn about different categories of uncertainty (stochastic, epistemic, ... Goal of uncertainty modelling Aims of quantitative uncertainty assessments: ▷ understand the influence of uncertainties • help ... Learn about different categories of uncertainty (stochastic, epistemic, decision uncertainty), how uncertainty modelling is ...
w16143 Uncertainty and Economic Activity: Evidence from Business Survey Data. Bloom, Van Reenen, and Bond. w12383 Uncertainty ... The Impact of Uncertainty Shocks. Nicholas Bloom. NBER Working Paper No. 13385. Issued in September 2007. NBER Program(s): ... Uncertainty appears to jump up after major shocks like the Cuban Missile crisis, the assassination of JFK, the OPEC I oil-price ... "The Impact of Uncertainty Shocks," Econometrica, Econometric Society, vol. 77(3), pages 623-685, 05. citation courtesy of ...
... youve heard of Heisenbergs uncertainty principle. Its the canonical example of quantum weirdness, the strange idea that you ... What Uncertainty Means to Me-- And You, and the Universe. In chapter 2 of How to Teach Physics to Your Dog, theres a footnote ... The large degree of certainty with respect to the time of the note means a large degree of uncertainty with respect to the ... One should also bear in mind that the uncertainty creeps in not once but twice when you actually listen to the noise, rather ...
Human beings hate uncertainty but cannot escape it, particularly now that our species has become host to a virus thats never ... To cope, we have to learn to tolerate great uncertainty, while having faith that scientists will find treatments and/or a ... Some people are now coping with the discomfort of uncertainty by proclaiming the pandemic over, grabbing a beer, and jumping ...
Its saturated with the psychological distress of "causal uncertainty," or uncertainty about why things happen in our lives. ... Behavioural economics suggests uncertainty can exacerbate our biases like overconfidence, which can lead to entrepreneurship ... Its in this personal climate of uncertainty that were beginning to see a change in communication behaviours online, which ... This suggests that the ongoing uncertainty of Brexit is continuing the cycle of narrative polarisation, and taking us further ...
Two of Londons biggest house builders are set to post bumper profits, confounding concerns that the capitals property boom has slowed dramatically.
1990) Uncertainty: A Guide to Dealing with Uncertainty in Quantitative Risk and Policy Analysis (Cambridge Univ Press, ... Permanent Uncertainty: Nonresponse in Surveys. Permanent statistical uncertainty arises from incompleteness or inadequacy of ... Transitory Uncertainty: Revisions in National Income Accounts. Transitory statistical uncertainty arises, because data ... Conceptual Uncertainty: Seasonal Adjustment of Official Statistics. Conceptual uncertainty arises from incomplete understanding ...
This paper presents an approach to the prediction of mineral prospectivity that provides an assessment of uncertainty. Two feed ... These two memberships and their uncertainties are combined to predict mineral deposit locations. The degree of uncertainty of ... Uncertainties of type error in the prediction of these two memberships are estimated using multidimensional interpolation. ... Kraipeerapun P., Fung C.C., Brown W., Wong K.W., Gedeon T. (2006) Uncertainty in Mineral Prospectivity Prediction. In: King I ...
Judgment under Uncertainty. Heuristics and Biases. Edited by Daniel Kahneman Paul Slovic Amos Tversky. View list of ... Preface; Part I. Introduction: 1. Judgment under uncertainty: heuristics and biases Amos Tversky and Daniel Kahneman; Part II. ... and methods for correcting and improving judgments under uncertainty. About half of the chapters are edited versions of classic ... Causal schemas in judgments under uncertainty Amos Tversky and Daniel Kahneman; 9. Shortcomings in the attribution process: on ...
While these uncertainty budgets support the majority of the high-dose dosimetry services other uncertainties have been ... The tables below are the uncertainty budgets for the high-dose dosimetry services. Irradiation geometries have been established ... Alanine transfer dosimetry uncertainties are for pellet dosimeters only. ... While these uncertainty budgets support the majority of the high-dose dosimetry services other uncertainties have been ...
This was uncertainty of an entirely different order. This was me!. With experience you learn that the unlikely does sometimes ... Until recently, I was pretty confident that I was good at dealing with uncertainty. After all, I thought, it goes with the ... The common scenarios in general practice all involve weighing up probabilities and accepting varying degrees of uncertainty. ... Uncertainty-from different perspectives. BMJ 2001; 323 doi: https://doi.org/10.1136/bmj.323.7310.460a (Published 25 August 2001 ...
... Patrick Bolton, Neng Wang, Jinqiang Yang. NBER Working Paper No. 20610 ... w20038 Uncertainty, Financial Frictions, and Investment Dynamics. Bolton, Wang, and Yang. w20979 Optimal Contracting, Corporate ... "Investment under uncertainty with financial constraints," Journal of Economic Theory, .. Users who downloaded this paper also ... and corporate savings under uncertainty for a financially constrained firm, which features endogenous growth options, ...
Myanmars economy performed better in 2017/18 amidst growing global and domestic uncertainty, partially offsetting slower ... YANGON, May 17, 2018 - Myanmars economy performed better in 2017/18 amidst growing global and domestic uncertainty, partially ... and strong services growth despite a slight slowdown likely due to tourism and banking sector uncertainties, according to the ...
The manufacturing-uncertainty strategy works because it buries you in the facts, loses you in the woods of science. Sometimes, ... In his new book, Doubt is Their Product, David Michaels describes how the corporate practice of "manufacturing uncertainty" has ... All you have to do is selectively highlight uncertainty, selectively attack the existing studies one by one, and ignore the ... With his extensive chronicling of just how many times the manufacturing-uncertainty strategy has been used to make our world ...
And thats one of the reasons why in this first of a series of Webinars on CERC and Zika I wanted to talk about uncertainty ... And based on what we know now is a reasonable approach to a situation that has a great deal of uncertainty. Lets go to the ... I just want to talk a little bit about Zika and some of the uncertainties that exist out there. So we may have some general ... What Id like to do is to talk a little bit about beyond dealing with uncertainty, what we can do to act trustworthy. And one ...
... had rewritten a federal report to magnify the level of uncertainty on climate change came as no surprise. ... had rewritten a federal report to magnify the level of uncertainty on climate change came as no surprise. Uncertainty is easily ... Manufacturing uncertainty is a business in itself. You too can launch a pretty good campaign. All you need is the money with ... By definition, uncertainties abound in our work; theres nothing to be done about that. Our public health and environmental ...
Uncertainty makes us feel vulnerable, so we try to escape it any way we can. Sometimes we even settle for misinformation or bad ... Without uncertainty, wed never start a business or risk loving someone new. There are no guarantees when we step into the ... When Im deep in uncertainty about work, I can get impatient and snappy with the people who mean the most to me -- and that ... Yet it really is possible to thrive amid uncertainty. Its not about getting advice you can trust; its about faith and self- ...
Uncertainty over Brexit is depressing economic growth in Britain, Chancellor Philip Hammond said on Friday after official data ... "Clearly that uncertainty is having a depressing effect on economic growth," Hammond told broadcasters during a trip to central ... LONDON (Reuters) - Uncertainty over Brexit is depressing economic growth in Britain, Chancellor Philip Hammond said on Friday ...
"The defunding efforts foster confusion and uncertainty," said Ian Hill, a senior fellow at the Urban Institute specializing in ...
  • The recent work of Owen [SIAM/ASA J. Uncertainty Quantification, 2 (2014), pp. 245--251] has introduced the. (siam.org)
  • A central problem in uncertainty quantification is how to characterize the impact that our incomplete knowledge. (siam.org)
  • Uncertainty Quantification (UQ) is a research area of growing theoretical and practical importance at the intersection of applied mathematics, probability, statistics, computational science and engineering (CSE) and many application areas. (warwick.ac.uk)
  • The topic for the 2015 school is Uncertainty Quantification for Physical Phenomena. (sintef.no)
  • This year's winter school covers the topic of uncertainty quantification for simulation of physical phenomena. (sintef.no)
  • Uncertainty quantification aims to answer the questions "How accurate are the results? (sintef.no)
  • This years winter school will lectured by the following experts on Uncertainty Quantification. (sintef.no)
  • Statistical analyses used to support these conclusions require uncertainty quantification (UQ), usually by estimating the relative standard deviation (RSD) in random and systematic errors associated with each measurement method. (hindawi.com)
  • Uncertainty quantification (UQ) is the science of quantitative characterization and reduction of uncertainties in both computational and real world applications. (wikipedia.org)
  • Computer experiments on computer simulations are the most common approach to study problems in uncertainty quantification. (wikipedia.org)
  • In the wake of Theresa May's failure to convince a skeptical parliament to back her deal, and Jeremy Corbyn's no-confidence motion in the government being voted down, uncertainty continues to reign in the two-year Brexit saga. (forbes.com)
  • It's in this personal climate of uncertainty that we're beginning to see a change in communication behaviours online, which signals a shift in how a post-Brexit British public will interact with the brands leading the economy out of this uncertain mess. (forbes.com)
  • Since the Brexit vote, people have had a stronger accuracy motivation and more information-seeking behaviour, which makes sense as people are trying to get rid of uncertainty distress. (forbes.com)
  • This suggests that the ongoing uncertainty of Brexit is continuing the cycle of narrative polarisation, and taking us further away from the cold, hard facts of Brexit reality. (forbes.com)
  • LONDON (Reuters) - Uncertainty over Brexit is depressing economic growth in Britain, Chancellor Philip Hammond said on Friday after official data showed lacklustre year-on-year expansion. (reuters.com)
  • He added: "With the uncertainty around Brexit at the moment my wife decided to apply for permanent residency . (telegraph.co.uk)
  • LONDON (Reuters) - Britain's construction companies in September reported the sharpest fall in activity since just after June 2016's Brexit vote, as clients put projects on hold due to uncertainty over the economy. (reuters.com)
  • The Bank said Brexit uncertainty had "intensified considerably" over the last month, adding falling oil prices were likely to drag inflation below its 2 percent target soon. (cnbc.com)
  • Brexit uncertainties have intensified considerably since the committee's last meeting," MPC members said in a summary of the December meeting. (cnbc.com)
  • Our overall EPU index co-varies positively with implied volatilities for Japanese equities, exchange rates and interest rates and with a survey-based measure of political uncertainty. (imf.org)
  • HONG KONG (MarketWatch) -- Pakistan shares slumped Thursday, sending the country's benchmark stock index down for a 15th session, as investors dumped shares on fears about political uncertainty and deteriorating economic conditions. (marketwatch.com)
  • Most of the Asian stock markets declined Tuesday, following losses on Wall Street overnight as increased political uncertainty in France and the Netherlands as well as disappointing eurozone manufacturing and services PMIs weighed on the sentiment. (ibtimes.com)
  • Proposals are being floated to unify Russia's myriad security, intelligence, and law-enforcement services under the Investigative Committee -- making control of the agency a key asset at a time of increased political uncertainty. (rferl.org)
  • YANGON, May 17, 2018 - Myanmar's economy performed better in 2017/18 amidst growing global and domestic uncertainty, partially offsetting slower growth in 2016/17. (worldbank.org)
  • Trade uncertainty and income inequality ," Working Papers 2017-03, University of Tasmania, Tasmanian School of Business and Economics. (repec.org)
  • Trade uncertainty and income inequality ," CAMA Working Papers 2017-24, Centre for Applied Macroeconomic Analysis, Crawford School of Public Policy, The Australian National University. (repec.org)
  • Trade Uncertainty and Income Inequality ," ANU Working Papers in Economics and Econometrics 2017-648, Australian National University, College of Business and Economics, School of Economics. (repec.org)
  • Trade Uncertainty and Income Inequality ," Globalization Institute Working Papers 306, Federal Reserve Bank of Dallas, revised 01 Mar 2017. (repec.org)
  • Learn about different categories of uncertainty (stochastic, epistemic, decision uncertainty), how uncertainty modelling is used in risk assessment, and different levels of sophistication in uncertainty representation in risk analysis. (slideshare.net)
  • Epistemic and aleatoric uncertainty. (warwick.ac.uk)
  • Uncertainty refers to epistemic situations involving imperfect or unknown information. (wikipedia.org)
  • Epistemic uncertainty Epistemic uncertainty is also known as systematic uncertainty, and is due to things one could in principle know but do not in practice. (wikipedia.org)
  • It is the essence of medical practice to live with uncertainty and to be forced to make decisions on the basis of incomplete knowledge. (washingtonpost.com)
  • Cognitive-behavioral therapy (CBT), specifically exposure response prevention (ERP) therapy not only helps sufferers face their fears, but also gives them the tools needed to learn to live with uncertainty. (psychcentral.com)
  • Though this therapy can initially be anxiety-provoking, the payoff is huge, as being able to live with uncertainty allows them to let go of the "what ifs" of the past and future and just live mindfully in the present. (psychcentral.com)
  • The future direction of China is the "major" source of uncertainty facing the global economy at the moment, according to billionaire investor George Soros. (cnbc.com)
  • We show that gain variability of individual neurons is tuned to stimulus uncertainty, that this tuning is specific to the features encoded by these neurons and largely invariant to the source of uncertainty. (nature.com)
  • As predicted, we found that gain variability selectively depends on stimulus uncertainty, and that this selectivity is roughly invariant to the source of uncertainty. (nature.com)
  • Systematic deviations which remain unchanged in repeated measurements are another source of uncertainty. (ptb.de)
  • We develop new economic policy uncertainty (EPU) indices for Japan from January 1987 onwards building on the approach of Baker, Bloom and Davis (2016). (imf.org)
  • Caution remained amid lingering uncertainties over potential trade negotiations between China and the United States. (nasdaq.com)
  • When the variables are the values of experimental measurements they have uncertainties due to measurement limitations (e.g., instrument precision ) which propagate due to the combination of variables in the function. (wikipedia.org)
  • It is different from the uncertainty of the measurement, which reflects only our lack of understanding of the error. (astm.org)
  • Second, simulation is used to evaluate the impact of uncertainty in measurement error RSDs on estimated nuclear material loss detection probabilities in sequences of measured material balances. (hindawi.com)
  • A complete measurement result hence requires a quantitative statement describing its associated uncertainty. (ptb.de)
  • Measurement uncertainty is particularly relevant in metrology, for example when the result of a measurement is traced back to an SI unit. (ptb.de)
  • The uncertainty about a measurement result is often due to random variations in measured data. (ptb.de)
  • In order to evaluate measurement uncertainties, statistical methods are employed. (ptb.de)
  • In metrology the uncertainty of a measurement result is often dominated by systematic deviations. (ptb.de)
  • The GUM can be seen as the de facto standard for the evaluation of measurement uncertainty in metrology. (ptb.de)
  • Although the terms are used in various ways among the general public, many specialists in decision theory, statistics and other quantitative fields have defined uncertainty, risk, and their measurement as: Uncertainty The lack of certainty, a state of limited knowledge where it is impossible to exactly describe the existing state, a future outcome, or more than one possible outcome. (wikipedia.org)
  • Measurement of uncertainty A set of possible states or outcomes where probabilities are assigned to each possible state or outcome - this also includes the application of a probability density function to continuous variables. (wikipedia.org)
  • Measurement of risk A set of measured uncertainties where some possible outcomes are losses, and the magnitudes of those losses - this also includes loss functions over continuous variables. (wikipedia.org)
  • The experimental uncertainty is inevitable and can be noticed by repeating a measurement for many times using exactly the same settings for all inputs/variables. (wikipedia.org)
  • Just because we cannot measure sufficiently with our currently available measurement devices does not preclude necessarily the existence of such information, which would move this uncertainty into the below category. (wikipedia.org)
  • Economist John B. Taylor of the Hoover Institution summed it up aptly: "Unpredictable economic policy - massive fiscal 'stimulus' and ballooning debt, the Federal Reserve's quantitative easing with multiyear near-zero interest rates, and regulatory uncertainty due to Obamacare and the Dodd-Frank financial reforms - is the main cause of persistent high unemployment and our feeble recovery. (humanevents.com)
  • Let's be clear about the difference between regulatory uncertainty and competitive uncertainty. (washingtonpost.com)
  • Quantitative uncertainty is usually expressed as a percentage error. (rsc.org)
  • Quantitative uses of the terms uncertainty and risk are fairly consistent from fields such as probability theory, actuarial science, and information theory. (wikipedia.org)
  • For the propagation of uncertainty through time, see Chaos theory § Sensitivity to initial conditions . (wikipedia.org)
  • In statistics , propagation of uncertainty (or propagation of error ) is the effect of variables ' uncertainties (or errors , more specifically random errors ) on the uncertainty of a function based on them. (wikipedia.org)
  • This research area covers all aspects of the effects of uncertainty and error on mathematical descriptions of real phenomena including theory and methods to describe quantitatively the origin, propagation, and interplay of different sources of error and uncertainty in analysis and predictions of the behavior of complex systems, in such areas as biological, chemical, engineering, financial, geophysical, physical, and social/political systems. (siam.org)
  • In the past, perturbation and stochastic collocation methods have been used for uncertainty propagation. (easychair.org)
  • We propose a model of visual cortex in which average neural response strength encodes stimulus features, while cross-neuron variability in response gain encodes the uncertainty of these features. (nature.com)
  • Since each of these factors is associated with increased information about the visual environment, response variability might represent stimulus uncertainty. (nature.com)
  • We propose that, while average response magnitude encodes stimulus features, variability in response gain encodes the uncertainty of these features. (nature.com)
  • This appears to be a general property of visual coding: we find that the gain variability of texture-selective neurons in V2 systematically increases with an image's textural uncertainty. (nature.com)
  • This model quantitatively matches the effects of stimulus uncertainty on response variability. (nature.com)
  • Data-driven decision makers are constantly faced with uncertainty, ambiguity, variability and even extremes. (informationweek.com)
  • Experimental uncertainty Also known as observation error, this comes from the variability of experimental measurements. (wikipedia.org)
  • So, here is my version of the educational uncertainty principle. (wired.com)
  • If you read about science at all, you've heard of Heisenberg's uncertainty principle. (scienceblogs.com)
  • In fact, the very fact that quantum particles have a wave nature creates the bridge between the weird quantum uncertainty principle and the classical uncertainty principle that you literally hear all the time. (scienceblogs.com)
  • It's the uncertainty principle and it's not even quantum! (scienceblogs.com)
  • Using the uncertainty principle find the energy required for the electron to be confined inside the hydrogen atom. (physicsforums.com)
  • ok im not sure how Δr (radius) goes into the uncertainty principle, i know how it works and how it shows that it can not be exactly precise but i just dont understant how Δr would fall in the equation is it just 1 x 10^-10 m[tex]\geq[/tex]4.14x10^-15 eV/12.56637061? (physicsforums.com)
  • Uncertainty principle Dilemma! (physicsforums.com)
  • Behavioural economics suggests uncertainty can exacerbate our biases like overconfidence, which can lead to entrepreneurship and innovation , but it can equally lead to short-term thinking and missing long-term opportunities by falling victim to loss aversion bias. (forbes.com)
  • In his new book, Doubt is Their Product , David Michaels describes how the corporate practice of "manufacturing uncertainty" has taken over our regulatory system and undermined our health. (prospect.org)
  • In his important new book, David Michaels calls the strategy "manufacturing uncertainty. (prospect.org)
  • But in significant part due to the manufacturing-uncertainty strategy, we now have the bureaucratic equivalent of clotted arteries. (prospect.org)
  • That's why it has mastered the art of manufacturing uncertainty, of demanding often impossible proof over common-sense precaution in the realm of public health. (latimes.com)
  • Manufacturing uncertainty is a business in itself. (latimes.com)
  • Three values are at the heart of the practice of science and engineering and are central to discovery and innovation: searching for uncertainty, recognition of ambiguity and learning from failure. (washingtonpost.com)
  • It means focusing on some topics to the exclusion of others, because there is a direct relationship between knowledge depth and the ability to recognize uncertainty and ambiguity. (washingtonpost.com)
  • The large degree of certainty with respect to the time of the note means a large degree of uncertainty with respect to the frequency of the note. (scienceblogs.com)
  • The degree of uncertainty of type vagueness for each cell location is estimated and represented in the form of indeterminacy-membership value. (springer.com)
  • Knightian uncertainty is named after University of Chicago economist Frank Knight (1885-1972), who distinguished risk and uncertainty in his 1921 work Risk, Uncertainty, and Profit: "Uncertainty must be taken in a sense radically distinct from the familiar notion of Risk, from which it has never been properly separated. (wikipedia.org)
  • On Bolivia's Altiplano, Aimara communities use crop and environmental diversity to devise production systems that cope with droughts, frosts, hail, floods and economic uncertainty. (iucn.org)
  • To many scientists and policymakers in Washington, the revelation this month that Philip Cooney, chief of staff for the White House Council on Environmental Quality, had rewritten a federal report to magnify the level of uncertainty on climate change came as no surprise. (latimes.com)
  • More importantly, a leader who is honest with her team about her level of uncertainty would gain a more engaged and loyal team. (forbes.com)
  • We then offer a protocol for summarizing the many possible sources of uncertainty in standard terms, designed to impose a minimal burden on scientists, while gradually educating those whose decisions depend on their work. (pnas.org)
  • Many problems in the natural sciences and engineering are also rife with sources of uncertainty. (wikipedia.org)
  • One way to categorize the sources of uncertainty is to consider: Parameter uncertainty This comes from the model parameters that are inputs to the computer model (mathematical model) but whose exact values are unknown to experimentalists and cannot be controlled in physical experiments, or whose values cannot be exactly inferred by statistical methods. (wikipedia.org)
  • Some people are now coping with the discomfort of uncertainty by proclaiming the pandemic over, grabbing a beer, and jumping into a pool with 500 other maskless people. (theweek.com)
  • Fewer smokers called quit-smoking hotlines last year and some smoked more, contributing to an unusual bump in cigarette sales - all in the middle of the stress, anxiety and uncertainty from the pandemic. (yahoo.com)
  • this is now referred to as Knightian uncertainty: Uncertainty must be taken in a sense radically distinct from the familiar notion of risk, from which it has never been properly separated. (wikipedia.org)
  • In economics, Knightian uncertainty is a lack of any quantifiable knowledge about some possible occurrence, as opposed to the presence of quantifiable risk (e.g., that in statistical noise or a parameter's confidence interval). (wikipedia.org)
  • However, the concept is largely informal and there is no single best formal system of probability and belief to represent Knightian uncertainty. (wikipedia.org)
  • in other words, Knightian uncertainty is presumed to not exist in day-to-day affairs, often with disastrous consequences. (wikipedia.org)
  • Aleatoric uncertainty Aleatoric uncertainty is also known as statistical uncertainty, and is representative of unknowns that differ each time we run the same experiment. (wikipedia.org)
  • in this Perspective, warming due to radiative forcing by CO2 can actually be calculated with far less uncertainty than current modeling approaches suggest. (eurekalert.org)
  • With minimal future volatility and potential highly scalable services, utility companies face a lot less uncertainty compared to other normal corporations. (reddit.com)
  • This workshop will highlight recent developments and research on topics related to model uncertainty and model choice in Statistics. (warwick.ac.uk)
  • We do expect government to reduce uncertainty in our lives in terms of safety and security in broad terms. (washingtonpost.com)
  • Market uncertainty doesn't constrain the economy but government regulations that reduce uncertainty by indirectly restricting competition would. (washingtonpost.com)
  • Until more sophisticated methods such as these can be incorporated into climate models, model parameters should be vetted against more accurate calculations, like LBL, to reduce uncertainty in climate projections. (eurekalert.org)
  • Reactive, distributed applications must decide how to handle uncertainty regarding the delivery of messages, including multiple delivery and out-of-order delivery. (infoq.com)
  • Three characteristics of leaders who handle uncertainty better than others consistently stand out during these workshops. (forbes.com)
  • Leaders who can handle uncertainty are not afraid to pose questions. (forbes.com)
  • As a result, communicating scientific uncertainty requires both simplifying and complicating normal scientific discourse. (pnas.org)
  • Uncertainty is easily manipulated, and Cooney -- a former lobbyist with the American Petroleum Institute, one of the nation's leading manufacturers of scientific uncertainty -- was highly familiar with its uses. (latimes.com)
  • There is a certain relationship between GUM S1 and a Bayesian uncertainty analysis. (ptb.de)
  • Propagating Uncertainty in Bayesian Networks by Probabilistic Logic Sampling (M. Henrion). (elsevier.com)
  • A process is implemented to propagate uncertainties inherent to the Statistical Energy Analysis (SEA) modeling practice to variance in predictions. (sae.org)
  • Information asymmetry Perfect information Emanuel Derman § Models.Behaving.Badly There are known knowns Uninformative prior Knight, F. H. (1921) Risk, Uncertainty, and Profit. (wikipedia.org)
  • Fisher, P.F.: Models of uncertainty in spatial data. (springer.com)
  • Much of scientists' own discourse is about uncertainty. (pnas.org)
  • At the other, it can omit vital uncertainties that are common knowledge within a field, hence go without saying, and uncertainties that a field routinely ignores, either because they appear unimportant or because its scientists have nothing to say about them. (pnas.org)
  • On the other hand, the uncertainties that scientists fail to mention must be uncovered. (pnas.org)
  • To cope, we have to learn to tolerate great uncertainty, while having faith that scientists will find treatments and/or a vaccine, and this bizarre era will end. (theweek.com)
  • While some scientists argue that uncertainty spices up sexual desire, Reis says his team's research results suggest the opposite holds true. (psychcentral.com)
  • Of course, uncertainty is more typical of initial romantic encounters when little is known about the new partner, compared to more advanced relationship stages, when the certainty about a partner's commitment and intentions is relatively high, the scientists note. (psychcentral.com)
  • Economists and management scientists continue to look at practical methodologies for decision under different types of uncertainty. (wikipedia.org)
  • Whilst Frank Knight's seminal book elaborated the problem, his focus was on how uncertainty generates imperfect market structures and explains actual profits. (wikipedia.org)
  • Convert an uncertainty quoted in a handbook, manufacturer's specification, calibration certificate, etc., that is a stated multiple of an estimated standard deviation to a standard uncertainty by dividing the quoted uncertainty by the multiplier. (nist.gov)
  • Some examples of this are the local free-fall acceleration in a falling object experiment, various material properties in a finite element analysis for engineering, and multiplier uncertainty in the context of macroeconomic policy optimization. (wikipedia.org)
  • Several earlier measurements of the relevant rate have shown variations of a factor of 3 or so, so that the uncertainty in the rate is not new. (realclimate.org)
  • Uncertainty can enter mathematical models and experimental measurements in various contexts. (wikipedia.org)
  • Interpolation uncertainty This comes from a lack of available data collected from computer model simulations and/or experimental measurements. (wikipedia.org)
  • Uncertainties of type error in the prediction of these two memberships are estimated using multidimensional interpolation. (springer.com)
  • When using a mathematical model, careful attention must be given to uncertainties in the model. (slideshare.net)
  • This effect is generally evaluated by propagating the uncertainties using the mathematical model. (easychair.org)
  • A first-order expansion solution is applied to integrate uncertainties in the power inputs of the system. (sae.org)
  • It's saturated with the psychological distress of "causal uncertainty," or uncertainty about why things happen in our lives. (forbes.com)
  • Using Twitter's search API as a database, the study measured how polarised the conversations were, the emotional responses to events causing high causal uncertainty, and conducted a regression analysis using a psycho-linguistic scoring system to understand the connection between language and behaviour. (forbes.com)
  • Markets mediate the uncertainty of survival and governments mediate the uncertainty of markets. (washingtonpost.com)
  • These behavioral effects imply that the neural circuits which mediate perception assess the uncertainty of sensory information. (nature.com)
  • Simulation helps in situations where many decision model factors have inherent uncertainty such as weather conditions, supplier costs, unknown market demand and competitor pricing. (informationweek.com)
  • We examine these three classes of decisions in terms of how to characterize, assess, and convey the uncertainties relevant to each. (pnas.org)
  • All you have to do is selectively highlight uncertainty, selectively attack the existing studies one by one, and ignore the weight of the evidence. (prospect.org)
  • It highlights the importance of permanent and transitory income uncertainty in the evaluation of growth in consumption inequality. (repec.org)
  • It is the variable probability distributions and evaluation across all possible combinations of these variables that allow for realistic evaluation of scenario uncertainty. (informationweek.com)
  • In metrology for nuclear safeguards, the term "uncertainty" characterizes the dispersion of estimates of a quantity known as the measurand, which is typically the amount of NM (such as U or Pu) in an item. (hindawi.com)
  • GUM S1 ) proposes a Monte Carlo Method (MCM) for the calculation of uncertainties. (ptb.de)
  • This is a challenging NDA application because often the detector is brought to the facility where ambient conditions can vary over time and because the items to be assayed are often heterogeneous in some way and/or are different from the items that were used to calibrate/validate and assess uncertainty in the NDA method. (hindawi.com)
  • However, executives also recognize that geopolitical uncertainty poses challenges, with close to half (43%) seeing it as a key risk. (ey.com)
  • This poses both uncertainty - whether the non-red balls are all yellow or all black - and probability - whether the ball is red or non-red, which is ⅓ vs. ⅔. (wikipedia.org)
  • Our study adds to evidence that credible policy plans and strong policy frameworks can favorably influence macroeconomic performance by, in part, reducing policy uncertainty. (imf.org)
  • Are you implying that government has a central role in reducing uncertainty in the economy? (washingtonpost.com)
  • Market Pulse: Rising uncertainty fuels growing. (reuters.com)
  • All science has uncertainty. (pnas.org)
  • As a result, conveying uncertainty is essential to science communication. (pnas.org)
  • Peer review scrutinizes the uncertainty in individual studies, protecting science from unwarranted faith in flawed results. (pnas.org)
  • In battles over regulating these and many other dangerous substances, money has bought science, and then science -- or, more precisely, artificially exaggerated uncertainty about scientific findings -- has greatly delayed action to protect public and worker safety. (prospect.org)
  • All of science is subject to such exploitation because all of science is fundamentally characterized by uncertainty. (prospect.org)
  • Every polluter and manufacturer of toxic chemicals understands that by fostering a debate on uncertainties in the underlying science and by harping on the need for more research -- always more research -- it can avoid debating the actual policy or regulation in question. (latimes.com)
  • Cousineau-Bouffard, G., "Implementation of an Uncertainty Analysis Process to SEA Predictions," SAE Technical Paper 2007-01-2312, 2007, https://doi.org/10.4271/2007-01-2312 . (sae.org)
  • Research is required to understand and statistically quantify the climate change induced uncertainty in future coastal ecosystem state. (tudelft.nl)
  • Consumption Inequality and Income Uncertainty ," The Quarterly Journal of Economics , Oxford University Press, vol. 113(2), pages 603-640. (repec.org)
  • Second order uncertainty In statistics and economics, second-order uncertainty is represented in probability density functions over (first-order) probabilities. (wikipedia.org)
  • Uncertainty in economics: a new approach. (wikipedia.org)
  • That is, exact predictions of policy outcomes are routine, while expressions of uncertainty are rare. (pnas.org)
  • However, Congress has required the CBO to make point predictions 10 y into the future, unaccompanied by measures of uncertainty. (pnas.org)
  • The common scenarios in general practice all involve weighing up probabilities and accepting varying degrees of uncertainty. (bmj.com)
  • If probabilities are applied to the possible outcomes using weather forecasts or even just a calibrated probability assessment, the uncertainty has been quantified. (wikipedia.org)
  • By revealing uncertainties, scientific discourse is an essential resource for communications about them. (pnas.org)
  • In the current discourse "uncertainty" a right-wing frame. (washingtonpost.com)
  • Krouskos says: "Current geopolitical uncertainty is undoubtedly front of mind for all CEOs. (ey.com)
  • The major uncertainty facing the world today is not the euro but the future direction of China. (cnbc.com)
  • Above all, it is a powerful metaphor for situations governed by uncertainty, and as such, it offers a unique and transformative learning experience for leaders of all kinds, business executives in particular. (forbes.com)
  • We demonstrate that this behavior naturally arises from known gain-control mechanisms, and illustrate how downstream circuits can jointly decode stimulus features and their uncertainty from sensory population activity. (nature.com)
  • Uncertainty arises in partially observable or stochastic environments, as well as due to ignorance, indolence, or both. (wikipedia.org)