RateMyProfessors.com. A popular website among college students is RateMyProfessors.com (RMP). Established over 10 years ago, RMP allows students to post quantitative ratings of their instructors. In Practical Assessment, Research and Evaluation (May 2007), University of Maine researchers investigated whether instructor ratings posted on RMP are correlated with the formal in-class student evaluations of teaching (SET) that all universities are required to administer at the end of the semester. Data collected for n = 426 University of Maine instructors yielded a correlation between RMP and SET ratings of .68.
(a) Give the equation of a linear model relating SET rating (y) to RMP rating (x).
(b) Give a practical interpretation of the value r = .68.
(c) Is the estimated slope of the line, part a, positive or negative? Explain.
(d) A test of the null hypothesis H0: ρ = 0 yielded a p-value of .001. Interpret this result.
(e) Compute the coefficient of determination, r2, for the regression analysis. Interpret the result.