“I have 5 groups of 10 cases in my data. How can I draw a stratified random sample from these cases? That is, from groups 1 through 5 I’d like to draw exactly 5, 4, 5, 6 and 3 cases at random. What’s an efficient way to do this?” Before and after drawing our stratified […]
Introduction Popular statistical procedures such as ANOVA, a chi-square test or a t-test quietly rely on the assumption that your data are a simple random sample from your population. Violation of this assumption may result in biased or even nonsensical test results and few researchers seem to be aware of this. Plenty of reasons for a brief discussion of simple […]
