Is Online Teacher Rating Service Accurate?

“Complaints about RateMyProfessors.com are widespread. Because the site doesn’t seek representative samples of students, or even ensure that students are ranking professors whose courses they have taken, a challenging professor may receive low scores from students who never did the work and an instructor who gives everyone A’s may be nominated for professor of the year. Studies have found that the best way to score well on RateMyProfessors.com is to look “hot” and be an easy grader. So what does it mean if RateMyProfessors.com has a high correlation with the kinds of student evaluations that colleges see as more valid?”