This article was originally published on Built In by Eric Kleppen. Variance is a powerful statistic used in data analysis and machine learning. It is one of the four main measures of variability along ...

Variance is a statistical calculation that numerically describes the amount of variation in a data set. If values in a data set wildly fluctuate, variance would be high and predictions based on the ...

Sample size determination is an important issue in planning research. In the context of one-way fixed-effect analysis of variance, the conventional sample size formula cannot be applied for the ...

Over-dispersed count data are frequently observed in clinical trials where the primary endpoint is occurrence of clinical events. Sample sizes of comparative clinical trials with these data are ...

Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...

A stock's historical variance measures the difference between the stock's returns for different periods and its average return. A stock with a lower variance typically generates returns that are ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Somer G. Anderson is CPA, doctor of ...