GPA and major#

Undergraduate students taking an introductory statistics course at Duke University surveyed their GPA and major. The side-by-side box plots show the distribution of GPA among three groups of majors. Also provided is the ANOVA output.

Part 1#

What is the p value of the hypothesis test?

Answer Section#

Part 2#

Using \(H_0\): Average GPA is the same for all majors. \(H_A\): At least one pair of means are different, what is the conclusion of the hypothesis test?

Answer Section#

  • Since p-value \(<\) 0.05, we reject \(H_0\). The data provides convincing evidence of a difference between the average GPAs across three groups of majors.

  • Since p-value \(>\) 0.05, fail to reject \(H_0\). The data do not provide convincing evidence of a difference between the average GPAs across three groups of majors.

  • The data is insufficient to get the hypothesis test significance.

Part 3#

How many students answered these questions on the survey, i.e. what is the sample size?

Answer Section#

Please enter a numeric value in.

Attribution#

Problem is from the OpenIntro Statistics textbook, licensed under the CC-BY 4.0 license.
Image representing the Creative Commons 4.0 BY license.