Task 1:
As a preliminary analysis you use independent-samples t-tests to examine potential differences between the No drug and Cannabis User groups on the BIS (BIS) and BAS (BAS) measures. You can assume normality.
Task 2:
Perform a mixed-ANOVA with ‘Group’ as the between-subject variable (2 levels) and ‘Block’ defined as the within-subjects Factor (5 levels). For the within-subjects Factor, you use the 5 Block measures of decision-making performance (Block1to Block5). Make sure you also collect the following additional data:
1. Descriptive data.
2. Perform a ‘Repeated’ contrast on ‘Block’.
3. Ask for Marginal Means Main effects tests for Block (Sidak adjustment).
4. Block*Group interaction profile plot.
5. You can assume normality, but do test homogeneity of variance.
Perform follow-up analyses by using independent-samples t-tests to compare between the two groups over the 5 levels of the within-subjects Factor (Block).
Task 3:
You now perform a multiple regression to predict performance after 5 Blocks (Block5) experience of the task from two variables: Behavioural Approach (BAS) and Behavioural Inhibition (BIS). You use a Forced Entry method and examine the relationship in the two groups (use ‘Split file’ option). Ensure you collect the appropriate basic diagnostics and plots to assess the assumptions required of multiple regression.