Power Analysis

Introduction

The power of a study is the probability that the test will identify statistically significant results. It is the probability to reject the null hypothesis when it is wrong. It equals to one minus the type 2 error.

1. Significant level: \( alpha \) - type 1 error
   
2. Sample size
   
3. Effect Size
   

Methods

The t test for means

\( d=\frac{m_{a}-m_{b}}{\sigma} \)