I’d like to write a bit about measuring effect sizes and Cohen’s d. Introduction For our note let’s settle on a single simple example problem. We have two samples of real numbers a_1, …, a_n and b_1, …, b_n. All the a_i are mutually exchangeable or generated by an independent […]
In this note, we discuss the use of Cohen’s D for planning difference-of-mean experiments. Estimating sample size Let’s imagine you are testing a new weight loss program and comparing it so some existing weight loss regimen. You want to run an experiment to determine if the new program is more […]
Authors: John Mount and Nina Zumel. The p-value is a valid frequentist statistical concept that is much abused and mis-used in practice. In this article I would like to call out a few features of p-values that can cause problems in evaluating summaries. Keep in mind: p-values are useful and […]