Rather than personally reading the research instructions to each subject, an investigator has the subjects listen to a tape recording of the research instructions. In this case, the researcher is trying to optimize t by
A) driving the means further apart.
B) decreasing the variability of response within groups.
C) using a paired t test rather than an independent t test.
D) increasing the total size of the study.

Question

Quizplus · Accepted Answer

By using a tape recording of the research instructions, the researcher is standardizing the delivery of the instructions to each subject, which reduces the potential for experimenter effects or inconsistencies in delivery that could increase variability within groups. Therefore, the goal of the researcher is likely to decrease the variability of response within groups, which is best served by option B.

Rather Than Personally Reading the Research Instructions to Each Subject