Suppose a group of 900 smokers (who all wanted to give up smoking) were randomly assigned to receive an antidepressant drug or a placebo for six weeks. Of the 450 patients who received the...

 Suppose a group of 900 smokers (who all wanted to give up smoking) were randomly assigned to receive an antidepressant drug or a placebo for six weeks. Of the 450 patients who received the antidepressant drug, 111 were not smoking one year later. Of the 450 patients who received the placebo, 159 were not smoking one year later. Given the null hypothesis H0:(Pdrug−Pplacebo)=0 and the alternative hypothesis Ha:(Pdrug−Pplacebo)≠0, conduct a test to see if taking an antidepressant drug can help smokers stop smoking. Use α=0.01,

(a) The test statistic is __________

(b) The P-value is _________

(c) The final conclusion is



A.There is not sufficient evidence to determine whether the antidepressant drug had an effect on changing smoking habits after one year.

B.There seems to be evidence that the patients taking the antidepressant drug have a different success rate of not smoking after one year than the placebo group.