Concept explainers
RateMyProfessors.com. A popular Web site among college students is RateMyProfessors.com (RMP). RMP allows students to post quantitative ratings of their instructors. In Practical Assessment, Research & Evaluation (May 2007), 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
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
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