Student ratings soar when professor uses enthusiasm.

Attention teachers far and wide: It may not be so much what or how you teach that will reap high student evaluations, but something as simple as an enthusiastic tone of voice. And beware, administrators, if you use student ratings to judge teachers: Although student evaluations may be systematic and reliable, a study has found that they can be totally invalid. Yet many schools use them to determine tenure, promotion, pay hikes, and awards.

These warnings stem from a new study in which a Cornell professor taught the identical course twice with one exception - he used a more enthusiastic tone of voice the second semester - and student ratings soared on every measure that second semester.

Those second-semester students gave much higher ratings not only on how knowledgeable and tolerant the professor was and on how much they say they learned, but even on factors such as the fairness of grading policies, text quality, professor organization, course goals, and professor accessibility.

And although the 249 students in the second-semester course said they learned more than the 229 students the previous semester believed they had learned, the two groups performed no differently on exams and other assessment measures.

"This study suggests that factors totally unrelated to actual teaching effectiveness, such as the variation in a professor's voice, can exert a sizable influence on student ratings of that same professor's knowledge, organization, and grading fairness," says Wendy Williams, associate professor of human development. Her colleague and co-author, Stephen J. Ceci, professor of human development, was the teacher evaluated by the students in a course on developmental psychology that he has taught for almost 20 years.

"The effect of the presentation style also colored students' reactions to factors unrelated to the teaching, such as the quality of the textbook and the teaching aids used," she adds. Yet the textbook and teaching aids were the same both semesters.

The researchers note that ...