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) change the testing procedures to increase the variability of the test scores.
D) increase the sample size of children tested.

Question

Quizplus · Accepted Answer

Increasing the sample size would decrease the standard error of the mean, making the estimate of the population mean more accurate. Testing children in a different district or changing the testing procedures may not address the issue of a large standard error of the mean. Computing a confidence interval can provide information on the precision of the estimate, but it does not directly influence the size of the standard error of the mean.

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