A researcher has children watch 30 minutes of violent television, and then counts the number of times they hit each other afterward in a one-hour play period as a measure of aggression. The researcher concludes that television violence causes aggression. However, this conclusion may be invalid because

Question

Quizplus · Accepted Answer

The absence of a control group means that there is no way to compare the behavior of the children who watched violent television to the behavior of children who did not. Without a control group, it is difficult to determine whether the violent television caused the aggressive behavior or if it was due to some other factor.

A Researcher Has Children Watch 30 Minutes of Violent Television