Wading Through the Data Swamp:
Program Evaluation 201
Supplements
The t-Test of Differences Between Means:
Paired Sample t-Test for Participant Pre- and Posttests
Step 5: Square the sum of the X values. Then divide by the n value.


1089/50 = 21.78
You will use this value in step 7 as part of the sum of squares calculation.








