506 Week 6 Discussion

As a criminologist, you are interested in the factors related to juvenile offending. You think that time spent studying influences delinquent behavior. In a group of 21 high school students, you collect information about the number of times a juvenile has broken curfew this month and how much time they spend studying this month. We break the sample into three groups, those who spend no time studying, those who spend less than 1 hour per day, those who spend more than 1 hour per day).

Time Spent Studying
No Time	Less than 1 Hour	More than 1 Hour
10	5	7
10	1	5
30	4	1
10	1	2
2	10	5
15	5	2
5	2	1
Σ = 82	Σ = 28	Σ = 23

a) What are the independent and dependent variables?

b) Compute the mean number of times each group broke curfew.

c) Compute the Grand Mean.

d) Using a significance level of .05, test the null hypothesis that the groups are equal against the alternative that at least one is different.