A professor invites students who did poorly on the first test to attend a special review session before the second test.Most do better on the second test.What conclusion,if any,can we draw,and why?
A)We conclude that the study session helped, because the scores improved.
B)We conclude that the most motivated students attended the review session, because scores improved.
C)We draw no conclusion, because the study has too many independent variables.
D)We draw no conclusion, because the study lacks a control group.

Question

A professor invites students who did poorly on the first test to attend a special review session before the second test.Most do better on the second test.What conclusion,if any,can we draw,and why?​
A)We conclude that the study session helped, because the scores improved.
B)​We conclude that the most motivated students attended the review session, because scores improved.
C)​We draw no conclusion, because the study has too many independent variables.
D)​We draw no conclusion, because the study lacks a control group.

Quizplus · Accepted Answer

The improvement in scores alone does not definitively indicate the cause of the improvement. Without a control group (students who did poorly but did not attend the session), it's impossible to determine if the review session was the reason for the improved scores or if other factors were at play.

A Professor Invites Students Who Did Poorly on the First