Chapter 8, Problem 8.8P

As the director of the local Boys Club, you have claimed for years that membership in your club reduces juvenile delinquency. Now a cynical member of your funding agency has demanded proof of your claim. Random samples of members and non- members are gathered and interviewed with respect to their involvement in delinquent activities. Each respondent is asked to enumerate the number of delinquent acts he has engaged in over the past year. The average numbers of admitted acts of delinquency are reported below. What can you tell the funding agency?

Sample 1 (Members)	Sample 2 (Nonmembers)
${\bar{X}}_1=10.3$	${\bar{X}}_2=12.3$
$s_1=2.7$	$s_2=4.2$
$N_1=40$	$N_2=55$