A Gentle Introduction to Statistics Using SASⓇ Studio

Chapter 9: Comparing More Than Two Means (ANOVA)

Introduction

Getting an Intuitive Feel for a One-Way ANOVA

Performing a One-Way Analysis of Variance

Performing More Diagnostic Plots

Performing a Nonparametric One-Way Test

Conclusion

Chapter 9 Exercises

Introduction

When you want to compare means in a study where there are three or more groups, you cannot use multiple t tests. In the old days (even before my time!), if you had three groups (let’s call them A, B, and C), you might perform t tests between each pair of means (A versus B, A versus C, and B versus C). With four groups, the situation gets more complicated; you would need six t tests (A versus B, A versus C, A versus D, B versus C, B versus D, and C versus D). Even though no one does ...