# Chapter 13: Comparing Three or More Means

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In Section 11.3, we compared two means from independent populations. What if we have more than two means to compare?

Suppose you own a chain of four boutique resale clothing shops. All four have been open for at least three years, and you want to do some analysis regarding their performance. You suspect that the managers at the four shops are not hiring staff of equal quality, so you take a sample of the weekly sales amounts for the employees at each location. You want to determine if any location is performing statistically lower than any of the others.

Using the strategies from Section 11.3, this would mean **six hypothesis tests** - one for each comparison (shop 1 vs. shop 2, shop 1 vs. shop 3, etc.). There has to be a better way! This is what One-Way Analysis of Variance is.

If you're ready to begin, just click on the "start" link below, or one of the section links on the left.