To compute the necessary sample size for an interval estimate of a population mean, all of the following procedures are recommended when σ is unknown except
A) use the estimated σ from a previous study.
B) use the sample standard deviation from a preliminary sample.
C) use judgment or a best guess.
D) use .5 as an estimate.

Question

To compute the necessary sample size for an interval estimate of a population mean, all of the following procedures are recommended when σ is unknown except​
A) ​use the estimated σ from a previous study.
B) ​use the sample standard deviation from a preliminary sample.
C) ​use judgment or a best guess.
D) use .5 as an estimate.

Quizplus · Accepted Answer

Using .5 as an estimate is not a recommended procedure for estimating the population standard deviation when σ is unknown.

To Compute the Necessary Sample Size for an Interval Estimate