Do Power Calculation Before Data Collection, Not After – With Downloadable R Code Notebook

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Justin Belair

Biostatistician in Science & Tech | Consultant | Causal Inference Specialist | Founder & Editor @ biostatistics.ca

Table of Contents

Don’t Compute the Statistical Power of Your Experiment…Even if SPSS Allows It And Your Editor Requires It!

Introduction

Download the R Markdown notebook here used to generate this blog post and practice your R skills for free!

Some widely used statistical tools, e.g. the AB testing significance calculator from Survey Monkey or even respectable (?) software like SPSS, provide a value of observed (or post-hoc) power computed from the data - see images below.