An unbiased estimator is:
A) any sample statistic used to approximate a population parameter.
B) a sample statistic that has an expected value equal to the value of the population parameter.
C) a sample statistic whose value is usually less than the value of the population parameter.
D) any estimator whose standard error is relatively small.

Question

Quizplus · Accepted Answer

An unbiased estimator is a sample statistic that has an expected value equal to the value of the population parameter. This means that, on average, the estimator will produce an estimate that is equal to the true value of the parameter being estimated. Option A is true but not precise. Option C is incorrect, an estimator whose value is usually less than the value of the population parameter can be biased. Option D is incorrect, a small standard error does not necessarily imply an estimator is unbiased.

An Unbiased Estimator Is