According to a recent poll by Gallup.com, 59% of Americans believe that the amount they pay in income taxes is fair. The survey was based on a sample 1017 American adults. If the pollsters talked to ...

Central Limit Theorem: A sampling distribution of the mean is approximately normally distributed if the sample size is sufficiently large. This is true no matter what the population distribution is.

The aim of this paper is to provide an overview of sample size estimations for the most frequent type of group studies that result in continuous, binary and ordered categorical outcomes. In recent ...