Calculate the Spearman Rank Order Correlation coefficient for the given pretest and posttest scores, showing the steps involved.

1d. Spearman Rank Order Correlation

To establish the degree of correlation between the pretest and posttest scores using Spearman's rank order correlation, we first rank the scores for Pretest (R1) and Posttest (R2), calculate the difference in ranks ($d$), square the differences ($d^2$), and then sum them ($\sum d^2$).

Step 1: Rank the Pretest (R1) and Posttest (R2) scores.
When ties occur, the average of the ranks that would have been assigned is used.

| Pretest (X) | Posttest (Y) | Rank (R1) | Rank (R2) | $d = R1 - R2