Computing the necessary sample size for an interval estimate of a population proportion requires a planning value for $\bar{p}$ . In case of any uncertainty about an appropriate planning value, we know the value that will provide the largest sample size for a given level of confidence and a given margin of error is
A) .10
B) .50
C) .90
D) 1

Question

Quizplus · Accepted Answer

The value of $\bar{p}$ that will provide the largest sample size for a given level of confidence and a given margin of error is 0.50. This is because the formula for determining sample size in this context includes the term $\bar{p}(1-\bar{p})$, which reaches its maximum value when $\bar{p} = 0.50$, making the product $\bar{p}(1-\bar{p}) = 0.25$ the largest possible. This results in the largest sample size needed to achieve the desired confidence level and margin of error.

Computing the Necessary Sample Size for an Interval Estimate of a Population