In a research study, participants are told that Louis has lived in Boston his whole life. They are then asked which is more likely: A) Louis is a baseball fan, or B) Louis is a baseball fan who roots for the Boston Red Sox. Which of the following is true?
A) Participants who answer 'A' are correct.
B) Participants who answer 'A' have committed the conjunction fallacy.
C) Participants who answer 'B' are demonstrating belief perseverance.
D) Participants who answer 'B' have committed the conjunction fallacy.

Question

Quizplus · Accepted Answer

Participants who answer 'B' have committed the conjunction fallacy, which is the tendency to believe that the co-occurrence of two events is more likely than the occurrence of one event alone, even when there is no logical basis for this belief. In this case, it is more likely that Louis is a baseball fan in general than that he is both a baseball fan and a fan of a specific team like the Boston Red Sox. Answer A does not reflect the conjunction fallacy but is not necessarily correct either, as there is no information to suggest that Louis likes baseball more than any other sport.

In a Research Study, Participants Are Told That Louis Has