After grading an examination, an instructor realizes her class is comprised of students who either completely understand the material or do NOT understand the material at all. She reaches this conclusion because the shape of the distribution of exam scores is ______.
A) bimodal
B) flat
C) skewed
D) normal

Question

Quizplus · Accepted Answer

A bimodal distribution is characterized by having two distinct peaks or modes, which suggests that the data is coming from two different populations. In this case, one peak would represent the students who completely understand the material and the other peak would represent the students who do not understand it at all. A flat distribution would suggest that all students performed similarly, while a skewed distribution would suggest that there is an uneven spread of scores. A normal distribution would suggest that there is a typical range of scores, which may or may not indicate understanding of the material.

After Grading an Examination, an Instructor Realizes Her Class Is