Method for estimating variance of several different populations
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In statistics, pooled variance (also known as combined variance, composite variance, or overall variance, and written ) is a method for estimating variance of several different populations when the mean of each population may be different, but one may assume that the variance of each population is the same. The numerical estimate resulting from the use of this method is also called the pooled variance.
Under the assumption of equal population variances, the pooled sample variance provides a higher precision estimate of variance than the individual sample variances. This higher precision can lead to increased statistical power when used in statistical tests that compare the populations, such as the t-test.
The square root of a pooled variance estimator is known as a pooled standard deviation (also known as combined standard deviation, composite standard deviation, or overall standard deviation).
the pooledvariance. Under the assumption of equal population variances, the pooled sample variance provides a higher precision estimate of variance than...
generalizing number of standard deviations to the mean Mean absolute error Pooledvariance Propagation of uncertainty Percentile Raw data Reduced chi-squared...
Variance-stabilizing transformation Correlation Distance variance Explained variancePooledvariance Pseudo-variance Wasserman, Larry (2005). All of Statistics: a...
sizes across the G groups are equal, then the two statistics coincide. Pooledvariance Everitt, B. S. (2006). The Cambridge Dictionary of Statistics (3 ed...
Analysis of variance (ANOVA) is a collection of statistical models and their associated estimation procedures (such as the "variation" among and between...
complete models, the condition holds and thus simplified asymptotic variance is valid. Pooled QMLE is a technique that allows estimating parameters when panel...
the xi are typically the means of samples each of size m, s2 is the pooledvariance, and the degrees of freedom are ν = n(m − 1). The critical value of...
treatment of the error variance matrix. Panel data analysis has three more-or-less independent approaches: independently pooled panels; random effects...
interclass (Pearson) correlation is that the data are pooled to estimate the mean and variance. The reason for this is that in the setting where an intraclass...
the end of each round. Pooled mining (BPM), also known as "slush's system", due to its first use on a pool called "slush's pool', uses a system where older...
Assuming that the variance is not infinite and that the central limit theorem applies to the sample then using the delta method, the variance is Var ( H...
and variance for all of their games. The house edge tells them what kind of profit they will make as a percentage of turnover, and the variance tells...
of pooling as well). In addition to max pooling, pooling units can use other functions, such as average pooling or ℓ2-norm pooling. Average pooling was...
heterozygotes if the two populations were pooled. F-statistics introduced the idea of quantifying hierarchical concepts of variance and would become the foundation...
differ under equal means and different variances. Under a correct assumption of equal population variances a pooled estimate for σ is more precise. Hedges'...
(αβ)⁄SE Where SE is the pooled standard error term and SE = √α2 σ2β + β2σ2α and σ2β is the variance of β and σ2α is the variance of α. This t statistic...
+1⁄8 inch variance allowed.[citation needed] In the UK as well as a number of other British Commonwealth and European countries, the typical pool table is...
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