In medical investigations, the ratio is often ofmore interest than the difference (e.g.

Chapter 9, Problem 55

(choose chapter or problem)

In medical investigations, the ratio is often ofmore interest than the difference (e.g., individualsgiven treatment 1 are how many times as likely to recover asthose given treatment 2?). Let . When m and n areboth large, the statistic has approximately a normaldistribution with approximate mean value ln(u) and approximatestandard deviation .a. Use these facts to obtain a large-sample 95% CI formulafor estimating ln(u), and then a CI for u itself.b. Return to the heart-attack data of Example 1.3, and calculatean interval of plausible values for u at the 95%confidence level. What does this interval suggest aboutthe efficacy of the aspirin treatment?