2022 Introduction to Statistics in Research Mitchell 2nd ed

I N T R O T O R E S E A R C H : D A T A V I S U A L I Z A T I O N & C O M M O N S T A T T E S T S

Run Paired-t test Boxplots in SPSS

On the main menu, choose Analyze > Compare means > Paired Samples t-test 1) Then put posttest as variable 1 and pretest as variable 2. I did it this way so it the output would show a positive number since I’m assuming the posttest would be a better score than the pre-test. 2) Under options, make sure the confidence interval is at 95%, accept the default and select, “Continue” 3) Make sure “Estimate effect sizes” is checked and accept the default, then choose “OK”

Table 147: Paired-t test steps in SPSS version 27

Output Explanation SPSS version 27 gives you four tables

a) Paired Sample Statistics: Provides the mean and the sample size. Note that not all samples were used since it can only use, well pairs. If you didn’t have both a pretest score and a posttest score, it was not included in the statistic. Note that the mean is much higher for the posttest – just what we expected.

Table 148: SPSS Paired t-test, table 1 of 4

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