In a memory study, participants are assigned to three groups, ensuring that each group has equal number of males and females. In the first group participants expect to receive a memory enhancing drug and that's what they get. In the second group they expect to receive a memory enhancing drug but receive placebo. In the third group they are led to believe that they are to receive placebo, but they receive the drug. Performance on a memory task (number of objects correctly recalled) is measured for participants in each group either after 2 minutes delay, 10 minutes delay or 60 minutes delay.

Identify all the variables in the study. Describe each variable in terms of its type of measurement and its role in the study (use as many descriptors as you know e.g. ordinal, independent, within-subject, dichotomous etc...).

Which statistical procedure would you use to analyze the data? (6%)