Juvenile offenders According to an article in the Journal of Consulting and Clinical Psychology, Charles Borduin pioneered a treatment called Multisystemic Therapy (MST) as a way to prevent serious mental health problems in adolescents. The therapy involves a total support network including family and community, rather than the more common individual therapy (e.g., visits to a therapist). After a 22-year-long study, one notable fact was that while 15.5% of juveniles who received individual therapy were arrested for a violent felony, only 4.3% of the juveniles treated with MST had done so.

1. Suppose the results are based on sample sizes of 125 juveniles in each group. Create a 99% confidence interval for the reduction in violent felony rate when comparing MST to the traditional individual therapy.

2. Using your interval, is there evidence of a true reduction for the whole population? Which population is the study investigating?