Students were amazed when Professor Diaz walked into class on the first day of the semester and correctly "sensed" that two people in his class of 23 were born on the same day. The tendency to think that it is very unlikely that two people in a class of 23 could share the same birthday is an example of the:
A)belief-bias effect.
B)confirmation bias.
C)fallacy of positive instances.
D)overestimation effect.

Question

Quizplus · Accepted Answer

This is an example of the overestimation effect, where people overestimate the improbability of two people in a small group sharing the same birthday. The actual probability that at least two people in a group of 23 share the same birthday is over 50%, which is counterintuitive to many, leading to an overestimation of how unlikely it seems.

Students Were Amazed When Professor Diaz Walked into Class on the First