Here is the problem: If there is an actual large effect size, then you can detect this in small samples. However, the opposite is not true. In a small sample,

Here is the problem: If there is an actual large effect size, then you can detect this in small samples. However, the opposite is not true. In a small sample, spurious large effects are MORE likely, not less likely (outliers have a greater impact in a small sample). See: http://andrewgelman.com/2017/08/16/also-holding-back-progress-make-mistakes-label-correct-arguments-nonsensical/ http://andrewgelman.com/2017/08/16/also-holding-back-progres...