CONTENTS

Table of Contents
Introduction

1. Descriptive Statistics in Evaluation
2. Subgroup Analysis
3. Variable - Are They Related?
4. Correlation
5. The t-Test of Difference Between Means

Supplements
Resources
Glossary

Wading Through the Data Swamp:
Program Evaluation 201

The t-Test of Differences Between Means:
Independent Samples t-Test for Pretest Data

Step 5: Square the sum of the scores for both groups.

This step is straightforward. All we have to do is square the sums from step 4. The square of 82 = 6724 (82 × 82). The square of 77 = 5929 (77 × 77). You will use these numbers in step 7, the sum of squares calculation.