A study shows that people who chew bubble gum have more cavities. Which criteria of casual inference does this example show?
A) The two variables are not correlated.
B) Multiple alternative explanations exist for the correlation.
C) The presumed cause precedes the presumed effect in time.
D) The study was conducted in an open environment.
E) The sample size is large enough.

Question

Quizplus · Accepted Answer

The study clearly shows that the presumed cause (chewing bubble gum) precedes the presumed effect (cavities). Making causal inferences requires establishing three things. First, that the two variables are correlated; second, that the presumed cause precedes the presumed effect in time; and third, that no alternative explanation exists for the correlation.

A Study Shows That People Who Chew Bubble Gum Have