Question

A professor expects that the grades on a recent exam are normally distributed with a mean of 80 and a standard deviation of 10. She records the actual distribution of grades and wants to compare it to the normal distribution.

Which of the following χ2 tests should be used in the situation above?

Select the correct answer below:
A. Test of Independence
B. Goodness-of-Fit Test
C. Test for Homogeneity

Answer 1

Answer:

B. Goodness-of-Fit Test

Step-by-step explanation:

Given that a professor expects that the grades on a recent exam are normally distributed with a mean of 80 and a standard deviation of 10.

She records the actual distribution of grades and wants to compare it to the normal distribution

For this expected values are to be got assuming normal and the observed and expected are used to calculate chi square.

Depending on the chi square statistic conclusion is made

Here the test to be done is

B) Goodness of fit test.

A is wrong because test of independence is done when there are more than one categorical variable in the rows.

C is wrong because here homogeneity is not tested

Only B is right.