Student Evaluations

Dave Munger of Cognitive Daily is discussing student evaluations in an article titled "Blink" methods now being applied in the classroom". The word "Blink" refers to the best-seller by Toronto author Malcolm Gladwell (an excellent book, BTW). Gladwell mentions a study by Nalini Ambady and Robert Rosenthal in (1992) where they exposed students to short video clips of a lecturer and asked for evaluations. The evaluations weren't much different from those done at the end of the term.

Unfortunately, Dave Munger seems to draw the wrong conclusions from this study as he explains in an earlier posting [The six-second teacher evaluation]. In that article from last May he says ...

So we do appear to be quite effective at making judgements about teaching ability even after viewing only a total of 6 seconds of actual teaching, and without even hearing the teacher's voice.

This is dead wrong. Students are good at evaluating something after six seconds but it sure as heck ain't teaching ability. It's probably whether the students like the teacher or not. We can make snap judgements about personality but not about ability. The correlation with end-of-term evaluations suggests that even after several months, students are still only evaluating the personality of the teacher and not teaching ability.

It makes no sense whatsoever to assume that students can judge how good a teacher you are from a six second video clip. How can they tell whether the lecturer is well prepared, knows the subject, writes fair exams, chooses the appropriate level of difficulty, and communicates important concepts?

The Canadian Association of University Teachers (CAUT) has developed a policy regarding student evaluations. The CAUT report discusses the pros and cons of student evaluations, including the Ambady and Rosenthal (1993) study. Here's what it says in footnote #10 ...

More recently, Ambady and Rosenthal (1993) report findings which point to the conclusion that student ratings of instructors can be strongly influenced by factors that probably bear only a slight relationship to critical dimensions of teaching effectiveness (though one must hasten to add that this is not the conclusion that Ambady and Rosenthal argue for in their study). They report that trained observers' evaluations of very brief segments (30 seconds or less) of silent videotape of college teachers yielded ratings of specific behaviors that correlated positively with students' ratings of the instructors. The experimenters found that appearing to be more active, confident, dominant, enthusiastic, likable, optimistic, supportive and warm, etc., in these "thin slices" of observation correlated positively with students' ratings of the instructors. In one of the experiments, student ratings of the instructors also were found to be "somewhat" influenced by the physical attractiveness of the teachers (p. 435). Whatever aspects of the teaching act have been accessed in this study, and no matter their positive relationship with student ratings, it must be obvious that there is more to effective teaching than demonstrating behaviors that can be documented in 30 seconds or less of silent videotape.

In his discussion of instructor personality and the politics of the classroom, Damron (1994) reviews the extensive literature that suggests that student ratings may be especially sensitive to students' perceptions of instructor personality or aspects of instructors' demeanour that bear little relationship to student learning or achievement.