Concept explainers
In medical investigations, the ratio θ = p1/p2 is often of more interest than the difference p1 − p2 (e.g., individuals given treatment 1 are how many times as likely to recover as those given treatment 2?). Let .
a. Use these facts to obtain a large-sample 95% CI formula for estimating ln(θ), and then a CI for θ itself.
b. Return to the heart-attack data of Example 1.3, and calculate an interval of plausible values for θ at the 95% confidence level. What does this interval suggest about the efficacy of the aspirin treatment?
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Probability and Statistics for Engineering and the Sciences
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