When to use which formula for sample variance?
Jan 7, 2025 · I also know that sample variance has the formula "Mean of the squares minus the mean squared". While calculating the sample variance of a given sample, I used both the …
why sample variance has has n-1 in the denominator?
Feb 25, 2016 · If the sample variance is larger than there is a greater chance that it captures the true population variance. That is why when you divide by $ (n-1)$ we call that an unbiased …
intuition - Intuitive explanation for dividing by $n-1$ when ...
Aug 28, 2015 · The variance estimator makes use of the sample mean and as a consequence underestimates the true variance of the population. Dividing by n-1 instead of n corrects for …
pooling - How to calculate pooled variance of two or more groups …
This formula works directly with the underlying sample means and sample variances of the two subgroups, and does not require intermediate calculation of the pooled sample mean.
Calculating the parameters of a Beta distribution using the mean …
Nov 29, 2017 · How can I calculate the $\alpha$ and $\beta$ parameters for a Beta distribution if I know the mean and variance that I want the distribution to have? Examples of an R command …
Variance of product of dependent variables - Cross Validated
In order to respond (offline) to a now-deleted challenge to the validity of this answer, I compared its results to direct calculation of the variance of the product in many simulations. It's not a …
Weighted Variance, one more time - Cross Validated
Unbiased weighted variance was already addressed here and elsewhere but there still seems to be a surprising amount of confusion. There appears to be a consensus toward the formula …
How exactly did statisticians agree to using (n-1) as the unbiased ...
Sample variance with with $1/n$ factor can be re-expressed as the average of all squared differences between all pairs points. Now notice that the pairs where the same point enters …
Explained variance score vs $R^2$ score - Cross Validated
Jul 16, 2021 · The explained variance formula compares the variance of your residuals to the variance, which sounds great. However, the documentation says exactly why such a metric is …
Difference between Pooled variance and Combined variance
Dec 17, 2021 · Could someone explain for me what the difference between Combined variance and pooled variance is? I have couple of groups (more than 2) with different sample size, I …