Q:

Two​ researchers, Jaime and​ Mariya, are each constructing confidence intervals for the proportion of a population who is​ left-handed. They find the point estimate is 0.14. Each independently constructed a confidence interval based on the point​ estimate, but​ Jaime's interval has a lower bound of 0.049 and an upper bound of 0.191​, while​ Mariya's interval has a lower bound of 0.079 and an upper bound of 0.201. Which interval is​ wrong? Why?

Accepted Solution

A:
Answer:Jaime's wrong, becuase the distance(absolute value) from the point estimate to the lower bound is different than he distance from the upper bound to the point estimate.Step-by-step explanation:The distance(absolute value) from the point estimate to the lower bound must be the same as the distance from the upper bound to the point estimate.The point estimate is 0.14.JaimeJaime's interval has a lower bound of 0.049 and an upper bound of 0.191upper - point = 0.191 - 0.14 = 0.051point - lower = 0.14 - 0.049 = 0.091Jaime's wrong, becuase the distance(absolute value) from the point estimate to the lower bound is different than he distance from the upper bound to the point estimate.MariyaJust to check.Mariya's interval has a lower bound of 0.079 and an upper bound of 0.201.upper - point = 0.201 - 0.14 = 0.061point - lower = 0.14 - 0.079 = 0.061Mariya has the same distances, so it is correct.