In testing the effect of noise on performance of a task,Ernie tests half of the participants in a cool,comfortable,quiet room,and the other half in a hot,noisy room.Ernie's failure to control for temperature of the room may result in a(n)
A) externally valid study.
B) internally valid study.
C) interaction.
D) confound.

Question

Quizplus · Accepted Answer

Ernie's failure to control for temperature of the room creates a confound, meaning that it is impossible to determine whether any differences in performance are due to the noise or the temperature. This weakens the internal validity of the study. External validity is not affected by this confound and an interaction between noise and temperature is not mentioned.

In Testing the Effect of Noise on Performance of a Task,Ernie