A social worker was interested in exploring whether there was a relationship between the severity of her clients' alcohol abuse problems and the degree to which they were depressed. (All scores in this exercise are fictitious, invented for the purpose of the exercise). Ten clients had been given the Michigan Alcoholism Screening Test (MAST), and their scores were as follows:
Client MAST Score
A 5
B 2
C 12
D 7
E 22
F 6
G 30
H 3
I 4
J 10
The same clients were also given the Beck Depression Inventory (BDI) , and received the following scores:
Client BDI Score
A 12
B 4
C 10
D 22
E 15
F 30
G 40
H 17
I 9
J 20
1. Construct a scattergram representing the relationship between scores on the MAST and on the BDI.
2. Based on eyeballing the scattergram, how strong would you expect the relationship between alcoholism and depression to be - (weak, moderate, strong)?
3. Construct a table showing each client's score on the MAST (use the MAST score as the X variable), the client's BDI score (Y variable), the square of each score, and the product obtained by multiplying the two scores for each client.
4. Using the numbers from your table, calculate Pearson's r for the relationship between alcoholism and depression.