In a study, 760 men with recurrent prostate cancer underwent radiation with or without a type of hormone-based chemotherapy. For 24 months, 384 subjects were given the chemotherapy and 376 subjects were given a placebo. The numbers who survived and did not survive after 12 years were tracked. The results are shown at the left. At α = 0.10, can you support the claim that the proportion of 12-year survivors is greater for subjects who were given the chemotherapy than for subjects who were given the placebo?

(a) Identify the claim and state H₀ and H_a, 

(b) Find the critical value(s) and identify the rejection region(s), 

(c) Find the standardized test statistic z, 

(d) Decide whether to reject or fail to reject the null hypothesis, and 

(e) Interpret the decision in the context of the original claim. Assume the samples are random and independent.

Transcribed Image Text:

How Many Subjects Survived After 12 Years and How Many Did Not? Did not survive, 108 91 Survived Survived 268 293 Chemotherapy Placebo