Question

A researcher examined the effect of lighting on learning. Randomly assigned participants learned material while using a 100 watt or a 125 watt bulb. There were no differences between the two groups. The nonsignificant results may have occurred because of:_______

A. a costly measure of learning.
B. insufficient strength of the manipulation.
C. selection differences.
D. all of these

Answer 1

Answer: B. insufficient strength of the manipulation

Step-by-step explanation: