The sample mean is a(n)_____ estimator of the population mean because it _____ the population mean across all possible random samples of a given size.
A)biased;underestimates
B)biased;overestimates
C)unbiased;equals
D)unbiased;underestimates

Question

Quizplus · Accepted Answer

An unbiased estimator is one that, on average, is equal to the population parameter it is estimating across all possible random samples of a given size. Therefore, since the sample mean is an unbiased estimator of the population mean, choice C is the correct answer as it states that the sample mean equals the population mean across all possible random samples of a given size. The other options, A, B, and D, are incorrect because they suggest that the sample mean is biased and either under or overestimate the true population mean.

The Sample Mean Is A(n)_____ Estimator of the Population Mean