When you construct a 90% confidence interval for a population proportion based on a sample, what is it that you are pretty sure is in your interval?
I. 90% of the sample data.
II. 90% of all sample proportions. III. The population proportion.
A) I only
B) I and II
C) II only
D) None
E) III only

Question

Quizplus · Accepted Answer

When you construct a 90% confidence interval for a population proportion based on a sample, the interval is designed to capture the true population proportion with a 90% degree of confidence. Therefore, we are pretty sure that the true population proportion lies within the interval. This means that the correct answer is E, as the interval estimates the value of the population proportion, not the sample data or sample proportions themselves.

When You Construct a 90% Confidence Interval for a Population