A researcher tests a sample of first-grade children for a school district to help the district identify areas in which the curriculum should be changed.The measure is a valid and reliable measure of intelligence.The researcher estimates the population mean for the intelligence scores and observes a large value for the standard error of the mean.The best thing the researcher could do to improve the estimate is
A)test children in a different,more heterogeneous school district.
B)compute a confidence interval.
C)increase the sample size of children tested.
D)change the testing procedures to increase the variability of the test scores.

Question

Quizplus · Accepted Answer

Increasing the sample size would decrease the standard error of the mean and improve the estimate. Testing children in a different school district or changing the testing procedures would not necessarily improve the estimate, and computing a confidence interval would simply provide a range of possible values for the population mean, rather than improving the estimate itself.

A Researcher Tests a Sample of First-Grade Children for a School