MONKEY4: The Effect of Monkey Tonic, Applied Monkey
Training, and Advanced Monkey Antics of Monkey IQ
Twelve monkeys are randomly assigned to one of four groups. Group 1 gets a preparation of Monkey tonic,
group 2 gets a course in Applied Monkey Training (AMT, patent pending), group 3 gets a course in advanced
monkey antics (AMA), and group 4 gets a sham treatment. Each subject has their Monkey Intelligence
Quotient (MIQ) measured at the beginning of the study (BASELINE) and after 12 weeks on their treatment
(WEEK12). Data are:
ID GROUP BASELINE WEEK12 DELTA
-- ----- -------- ------ -----
1 1 81 80 -1
2 1 95 91 -4
3 1 96 97 1
4 2 60 73 13
5 2 97 103 6
6 2 126 134 8
7 3 65 70 5
8 3 85 91 6
9 3 95 100 5
10 4 94 97 3
11 4 95 98 3
12 4 99 101 2
Exercises
- (1) Study Design: Consider the study's design. Is it experimental or observational? Are measurements paired
or independent (or both)? Identify research questions worthy of analysis. List three such questions.
- (2) Data Entry & Validation: Enter these data into a file. Document the data in the form of a code book.
Create value labels and range checks.
- (3) Compare the Groups at Baseline: Use summary statistics to compare the groups at baseline. Then,
perform an analysis of variance to assess differences. Perform post hoc comparisons if warranted.
- (4) Changes Within Groups: Determine whether there has been a significant change in MIQ scores within
each group. (Four separate paired t tests.) Clearly state your conclusions.
- (5) Compare the Change Between Groups: The DELTA variable is the difference in WEEK12 scores and
BASELINE scores. Explore these differences. Describe these differences. Test to see if these change differ
between groups. Perform post hoc comparisons, if warranted.