Although smoking has diminished in recent years, it is still problematic in the prison population.In an effort to reduce smoking among prisoners, a psychologist decided to evaluate two different treatments. In one, smokers heard a detailed explanation about the effects of cigarette smoke on the human body, accompanied by graphic slides of those effects. In the other treatment, smokers had daily phone conversations with a therapist who encouraged them get through that day without smoking. To control for effects of age, sex and smoking history, the psychologist assigned people to the experimental groups in pairs matched on those variables. The data, in the form of the number of hours without a cigarette following the treatment, are listed below:

3) Although smoking has diminished in recent years, it is still problematic in the prison population. In an effort to reduce smoking among prisoners, a psychologist decided to evaluate two different treatments. In one, smokers heard a detailed explanation about the effects of cigarette smoke on the human body, accompanied by graphic slides of those effects. In the other treatment, smokers had daily phone conversations with a therapist who encouraged them get through that day without smoking. To control for effects of age, sex and smoking history, the psychologist assigned people to the experimental groups in pairs matched on those variables. The data, in the form of the number of hours without a cigarette following the treatment, are listed below: Pair Explanation + Slides Daily Encouragement 105 122 98 86 121 127 99 92 OO JOUAWNG 65 85 130 152 108 92 57 63 a) Do the treatments lead to different lengths of time before prisoners start smoking again? (a = .05) (6 marks) b) Form the 99% confidence interval for the true difference between the two treatments