What factors inhibit the learning process in the classroom? To answer this question, researchers at Murray State University surveyed 40 students from a senior-level marketing class (Marketing Education Review). Each student was given a list of factors and asked to rate the extent to which each factor inhibited the learning process in courses offered in their department. A 7-point rating scale was used, where 1 = "not at all" and 7 = "to a great extent." The factor with the highest rating was instructor related: "Professors who place too much emphasis on a single right answer rather than overall thinking and creative ideas." Summary statistics for the student ratings of this factor are x̅ = 4.70, s = 1.62.
a. Conduct a test to determine if the true mean rating for this instructor-related factor exceeds 4. Use α = .05. Interpret the test results.
b. Examine the results of the study from a practical view, then discuss why "statistically significant" does not always imply "practically significant."
c. Because the variable of interest, rating, is measured on a 7-point scale, it is unlikely that the population of ratings will be normally distributed. Consequently, some analysts may perceive the test, part a, to be invalid and search for alternative methods of analysis. Defend or refute this argument.