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  • distributions
  • If there are n risky assets instead of just one, and if their returns are jointly elliptically distributed, then all portfolios can be characterized completely by their mean and variance-that is, any two portfolios with identical mean and variance of portfolio return have identical distributions of portfolio return-and all possible portfolios have return distributions that are location-scale-related to each other. (wikipedia.org)
  • 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)
  • inverse
  • The efficiency for a term is the fraction of the maximum possible precision (inverse variance) obtainable by estimating in just that stratum. (ethz.ch)
  • residuals
  • The total sum of squares - that is, \( {\sum}_{i=1}^5{\sum}_{j=1}^8{\left({y}_{ij}-\overline{y}..\right)}^2 \) - is 0.078 + 3.944 + 1.417, which can be decomposed into these three terms corresponding to variance described by treatment, variance described by airport, and residuals. (springer.com)
  • Since it is a non-parametric method, the Kruskal-Wallis test does not assume a normal distribution of the residuals, unlike the analogous one-way analysis of variance. (wikipedia.org)
  • portfolios
  • With Dantzig's help, Markowitz continued to research optimization techniques, further developing the critical line algorithm for the identification of the optimal mean-variance portfolios, relying on what was later named the Markowitz frontier. (wikipedia.org)
  • analyze
  • Multireader multicase (MRMC) variance analysis has become widely utilized to analyze observer studies for which the summary measure is the area under the receiver operating characteristic (ROC) curve. (osapublishing.org)
  • We apply bias-variance definitions to analyze quantitative modelling of amino acid pathways of Saccharomyces cerevisiae (yeast). (igi-global.com)
  • measures
  • Discriminant function analysis Repeated measures design Canonical correlation analysis Warne, R. T. (2014). (wikipedia.org)
  • 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)
  • 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)
  • 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)
  • 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)
  • estimate
  • Laplace soon knew how to estimate a variance from a residual (rather than a total) sum of squares. (wikipedia.org)
  • Tukey extended this method by assuming that if the replicates could be considered identically and independently distributed, then an estimate of the variance of the sample parameter could be made and that it would be approximately distributed as a t variate with n−1 degrees of freedom (n being the sample size). (wikipedia.org)
  • The basic idea behind the jackknife variance estimator lies in systematically recomputing the statistic estimate, leaving out one or more observations at a time from the sample set. (wikipedia.org)
  • From this new set of replicates of the statistic, an estimate for the bias and an estimate for the variance of the statistic can be calculated. (wikipedia.org)
  • Instead of using the jackknife to estimate the variance, it may instead be applied to the log of the variance. (wikipedia.org)
  • For many statistical parameters the jackknife estimate of variance tends asymptotically to the true value almost surely. (wikipedia.org)
  • 1918
  • Ronald Fisher introduced the term variance and proposed its formal analysis in a 1918 article The Correlation Between Relatives on the Supposition of Mendelian Inheritance. (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)
  • 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)
  • genetic
  • 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)
  • Peakall, R. and Smouse P.E. (2012) GenAlEx 6.5: genetic analysis in Excel. (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)
  • We extend MRMC variance analysis to binary data and also to generic study designs in which every reader may not interpret every case. (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)
  • After the test has been completed, you can perform further tests on the factors which contribute to the variability, or discover that there are more factors not captured in your data that are missing from your analysis. (shmula.com)
  • If your analysis shows a percentage of only 33%, likely you are missing some important variables from your data set, and should find ways to gather additional data and re-run your analysis. (shmula.com)
  • 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)
  • It consists of focus and analysis of statistically relevant anomalies in the data. (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)
  • 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)
  • 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)
  • mean
  • Computes a confidence interval on a variance component estimated as proportional to the difference in two mean squares in a balanced complete experimental design. (roguewave.com)
  • We use mean-variance analysis to demonstrate the importance of a hitherto neglected benefit of enticing MNEs to locate in small and medium-sized countries. (repec.org)
  • A successful grouping will split dogs such that (a) each group has a low variance of dog weights (meaning the group is relatively homogeneous) and (b) the mean of each group is distinct (if two groups have the same mean, then it isn't reasonable to conclude that the groups are, in fact, separate in any meaningful way). (wikipedia.org)
  • 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)
  • Mean-variance analysis redirects here. (wikipedia.org)
  • For mean-variance portfolio theory, see Modern portfolio theory or Mutual fund separation theorem. (wikipedia.org)
  • The two moments are almost always the mean-that is, the expected value, which is the first moment about zero-and the variance, which is the second moment about the mean (or the standard deviation, which is the square root of the variance). (wikipedia.org)
  • these employ mean-variance analysis, and focus on the mean and variance of a portfolio's final value. (wikipedia.org)
  • test
  • 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)
  • Calculations of the means and the variance are performed as part of the hypothesis test. (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)
  • variable
  • Variance can tell how volatile the random variable in question is. (chegg.com)
  • This analysis helps to determine if all categories or groups studied are the same within that variable (such as each country). (shmula.com)
  • 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)