Free reference · 596 entries
The words, before the course.
Short, plain definitions of the terms that turn up in statistics and data science — what they mean, and how they relate to each other. Nothing to sign in for.
10 of 596 entries under W
- Ward’s LinkageWard’s linkage is a method for hierarchical cluster analysis. The idea has much in common with analysis of variance (ANOVA).
- Weighted KappaWeighted kappa is a measure of agreement for Categorical data. It is a generalization of the Kappa statistic to situations in which the categories are not equal in some respect – that is, weighted by an…
- Weighted MeanThe weighted mean is a measure of central tendency. The weighted mean of a set of values is computed according to the following formula: where are non-negative coefficients, called “weights”, that are…
- Weighted Mean (Calculation)To simplify calculation of the weighted mean, weights are often standardized to make their sum equal to the unit value, i.e.
- White Hat BiasWhite Hat Bias is bias leading to distortion in, or selective presentation of, data that is considered by investigators or reviewers to be acceptable because it is in the service of righteous goals.
- White NoiseThe white noise is a stationary time series or a stationary random process with zero autocorrelation.
- Wilcoxon – Mann – Whitney U TestThe Wilcoxon-Mann-Whitney test uses the ranks of data to test the hypothesis that two samples of sizes m and n might come from the same population.
- Wilcoxon Rank SumsWilcoxon rank sums are two statistics T+ and T– computed from paired replicates data. Suppose we have two sets of pairs of measurements (xi,yi), i=1,…,N for each of N experimental units.
- Wilcoxon Signed Ranks TestThe Wilcoxon signed ranks test is aimed at testing a null hypothesis from paired replicates data – that both treatments are equivalent.
- Wilks’s LambdaWilks’s lambda is a general test statistic used in multivariate tests of mean differences among more than two groups.
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