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  • distributions
  • In decision theory, if all alternative distributions available to a decision-maker are in the same location-scale family, and the first two moments are finite, then a two-moment decision model can apply, and decision-making can be framed in terms of the means and the variances of the distributions. (wikipedia.org)
  • populations
  • If the group means are drawn from populations with the same mean values, the variance between the group means should be lower than the variance of the samples, following the central limit theorem. (wikipedia.org)
  • Variances of populations are equal. (wikipedia.org)
  • The jackknife is consistent for the sample means, sample variances, central and non-central t-statistics (with possibly non-normal populations), sample coefficient of variation, maximum likelihood estimators, least squares estimators, correlation coefficients and regression coefficients. (wikipedia.org)
  • components
  • In a mixed-design, you are taking repeated measures from the same participants and therefore the sum of squares can be broken down even further into three components: SSwithin-subjects (variance due to being in different repeated measure conditions), SSerror (other variance), and SSBT*WT (variance of interaction of between-subjects by within-subjects conditions). (wikipedia.org)
  • ratio
  • We would expect the F -ratio to be less than 1 only in unusual models with negative within-group correlations (for example, if the data y have been renormalized in some way, and this had not been accounted for in the data analysis). (springer.com)
  • F-ratio is a test statistic used specifically for analysis of variance, as the F score shows where the area of rejection for the null hypothesis begins. (wisegeek.com)
  • In the case of a unimodal variate the ratio of the jackknife variance to the sample variance tends to be distributed as one half the square of a chi square distribution with two degrees of freedom. (wikipedia.org)
  • model
  • Analysis of molecular variance (AMOVA), is a statistical model for the molecular variation in a single species, typically biological. (wikipedia.org)
  • For example, given a model with two inputs and one output, one might find that 70% of the output variance is caused by the variance in the first input, 20% by the variance in the second, and 10% due to interactions between the two. (wikipedia.org)
  • Xd}, and Y is a chosen univariate model output (note that this approach examines scalar model outputs, but multiple outputs can be analysed by multiple independent sensitivity analyses). (wikipedia.org)
  • While researching the then current understanding of stock prices, which at the time consisted in the present value model of John Burr Williams, Markowitz realized that the theory lacks an analysis of the impact of risk. (wikipedia.org)
  • standard
  • Variance analysis is the process of examining in detail each variance between actual and budgeted/expected/standard costs to determine the reasons why budgeted results were not met (material costs too high, sales prices too low, etc. (ventureline.com)
  • statistics
  • In this course, part two of a series, Professor Joseph Schmuller teaches you how to use statistics concepts and tools to perform analysis in Microsoft Excel. (lynda.com)
  • By the end of this course, you should have the foundational knowledge you need to take other statistics-related courses and perform basic analysis in the workplace. (lynda.com)
  • In statistics, analysis of rhythmic variance (ANORVA) is a method for detecting rhythms in biological time series, published by Peter Celec (Biol Res. (wikipedia.org)
  • At the same time, statistics is concerned with evidence-based reasoning, particularly with the analysis of data. (wikipedia.org)
  • data
  • In order to track underlying business developments from period to period, Yara's management also uses a variance analysis methodology, developed within the company ("Variance Analysis"), which involves the extraction of financial information from the accounting system, as well as statistical and other data from internal management information systems. (yara.com)
  • Now that the data is all properly stored in a data frame, we are ready to begin the analysis. (wisc.edu)
  • Any analysis should begin with a graphical exploration of the data. (wisc.edu)
  • Brandon D. Gallas, Gene A. Pennello, and Kyle J. Myers, "Multireader multicase variance analysis for binary data," J. Opt. (osapublishing.org)
  • He explains how to organize and present data and how to draw conclusions using Excel's functions, charts, and 3D maps and the Solver and Analysis ToolPak add-ons. (lynda.com)
  • The company specializes in the development and marketing of inexpensive and easy-to-use statistical software for scientists, as well as in data analysis consulting. (kovcomp.co.uk)
  • If data are ordinal, a non-parametric alternative to this test should be used such as Kruskal-Wallis one-way analysis of variance. (wikipedia.org)
  • Analysis of molecular variance inferred from metric distances among DNA haplotypes: application to human mitochondrial DNA restriction data" (Free full text). (wikipedia.org)
  • ANORVA is based on the premise that the variance in groups of data from rhythmic variables is low when a time distance of one period exists between the data entries. (wikipedia.org)
  • Analysis of Messy Data. (wikipedia.org)
  • This involves thinking about the nature and quality of the data and, where the data came from, choosing appropriate analyses and models, and interpreting the results in the context of the problem and given the constraints of the data. (wikipedia.org)
  • Microsoft Excel
  • An additional free statistical package, GenAlEx, is geared toward teaching as well as research and allows for complex genetic analyses to be employed and compared within the commonly used Microsoft Excel interface. (wikipedia.org)
  • Responses
  • Variance-based measures of sensitivity are attractive because they measure sensitivity across the whole input space (i.e. it is a global method), they can deal with nonlinear responses, and they can measure the effect of interactions in non-additive systems. (wikipedia.org)
  • test
  • B. Feng and X. Zhang, "Study on t-test, analysis of variance and multiple comparisons," Journal of Taiyuan Normal University (Natural Science Edition) , vol. 11, no. 4, pp. 46-49, 2012. (hindawi.com)
  • If the variances are not known to be equal, a generalization of 2-sample Welch's t-test can be used. (wikipedia.org)
  • He showed that under the usual departures (positive skew, unequal variances) "the F-test is conservative" so is less likely than it should be to find that a variable is significant. (wikipedia.org)
  • Therefore, a researcher might use sample contrasts between individual sample pairs, or post hoc tests using Dunn's test, which (1) properly employs the same rankings as the Kruskal-Wallis test, and (2) properly employs the pooled variance implied by the null hypothesis of the Kruskal-Wallis test in order to determine which of the sample pairs are significantly different. (wikipedia.org)
  • find
  • Management by exception focuses mainly on large adverse variances, to find the areas of business, which deviates from predetermined standards in a negative way. (wikipedia.org)
  • R1a1
  • J2a and R1a1 have similar Y-STR variances in the two studied populations (0.36 and 0.34), and their ages are roughly a third of those reported (with wide uncertainty), or about ~4ky. (blogspot.com)
  • The variance of R1a1 in the Balkans might have been enhanced by infiltrations of Indo-European speaking peoples between 2000 and 1000 BC, and by the Slavic migrations to the region in the early Middle Ages. (wikipedia.org)
  • differences
  • Several investigators have used meta-analysis to compare the results of studies of gender differences on various spatial tests and have concluded that the magnitude of the gender difference in spatial ability is decreasing over time. (springer.com)
  • Emergence and characterization of sex differences in spatial ability: A meta-analysis. (springer.com)
  • A meta-analysis of gender differences in spatial ability: Implications for mathematics and science achievement. (springer.com)
  • Since there are questions as to whether theories dealing with central themes, such as affect, cognition, conceptions of the self, and issues such as psychopathology, anxiety, and depression, may lack external validity when "exported" to other cultural contexts, cross-cultural psychology re-examines them using methodologies designed to factor in cultural differences so as to account for cultural variance. (wikipedia.org)
  • Although some critics have pointed to methodological flaws in cross-cultural psychological research and claim that serious shortcomings in the theoretical and methodological bases used impede rather than help the scientific search for universal principles in psychology, cross-cultural psychologists are turning more to the study of how differences (variance) occur, rather than searching for universals in the style of physics or chemistry. (wikipedia.org)
  • flaws
  • In October 2015, three years after the announcement of the initial finding, researchers from the University of Oxford published a paper entitled "Ghost in the Time Series", demonstrating flaws in the original analysis. (wikipedia.org)
  • Sources
  • The team made 459 observations of Alpha Centauri B's color spectrum over a four-year period, then used statistical filters to remove known sources of variance. (wikipedia.org)
  • The transformations filtered out other sources of radial-velocity variance, including effects of starspots, photospheric granulation and rotation, as well as interference from the neighboring star Alpha Centauri A. The final, derived radial-velocity measurements showed the periodic influence of the planet on the star, but were near the threshold of the HARPS instrument's sensory capabilities. (wikipedia.org)
  • It argues that shared family influences on g are substantial in childhood, but that in adults the environmental sources of variance are almost exclusively of the within-family kind. (wikipedia.org)
  • experiment
  • The computational analysis of an RNA-Seq experiment begins earlier: what we get from the sequencing machine is a set of FASTQ files that contain the nucleotide sequence of each read and a quality score at each position. (bioconductor.org)
  • 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
  • Later in 1970, several focus groups were performed where executives from eight industries were asked about their definition of risk resulting in semi-variance being a better indicator than ordinary variance. (wikipedia.org)
  • large
  • Its frequency peaks in Herzegovina (64%), and its variance peaks over a large geographic area covering B-H, Serbia, Hungary, Poland, the Czech Republic, and Slovakia. (wikipedia.org)
  • time
  • Analyses of the d' s computed for the studies revealed that the magnitude of the gender difference on the mental Rotations test has remained stable over time. (springer.com)
  • This is about the same time Harry Markowitz was developing mean-variance theory. (wikipedia.org)
  • matrix
  • The only information needed regarding the unknown parameters in the A and B matrices is the expected value and variance of each element of each matrix and the covariances among elements of the same matrix and among elements across matrices. (wikipedia.org)
  • If there is only one window, R 2 {\displaystyle \mathbf {R} _{2}} can be considered as the identity matrix and then CSP corresponds to Principal component analysis. (wikipedia.org)