Chapter 11.1, Problem 11E

Variability in GMAT Scores. In 2016, the Graduate Management Admission Council reported that the variance in GMAT scores was 14,660. At a recent summit, a group of economics professors met to discuss the GMAT performance of undergraduate students majoring in economics. Some expected the variability in GMAT scores achieved by undergraduate economics students to be greater than the variability in GMAT scores of the general population of GMAT takers. However, others took the opposite view. The file EconGMAT contains GMAT scores for 51 randomly selected undergraduate students majoring in economics.

1. a. Compute the mean, variance, and standard deviation of the GMAT scores for the 51 observations.
2. b. Develop hypotheses to test whether the sample data indicate that the variance in GMAT scores for undergraduate students majoring in economics differs from the general population of GMAT takers.
3. c. Use α = .05 to conduct the hypothesis test formulated in part (b). What is your conclusion?