In: Statistics and Probability
A researcher was interested in comparing the GPAs of students at two different colleges. Independent simple random samples of 8 students from college A and 13 students from college B yielded the following GPAs.
College A: 3.7, 3.2, 3.0, 2.5, 3.4, 2.8, 3.6, 2.7
College B: 3.8, 3.2, 3.0, 3.9, 3.8, 2.5, 2.8, 4.0, 3.6, 2.6, 4.0, 3.6, 3.9
Find a 95% confidence interval for the difference, μ1 - μ2, between the mean GPA of college A students and the mean GPA of college B students. Also, find the margin of error. What is the parameter of interest? What is the underlying distribution?