ANN ARBOR—Good instructors, have no fear: you can make up for a bad first impression.

A new University of Michigan study shows that while our first impressions of educators might affect our ratings of them, ultimately the quality of their instruction matters the most in student evaluations.

Psychologists have long known that first impressions correlate with students' end-of-term instructor evaluations. However, until now, it has not been known if that's because first impressions color a student's opinion of a teacher for long after, or if a first impression can actually provide evidence of instructor quality.

In other words, is a teacher who makes a bad first impression likely to continue to be a bad instructor throughout a course?

U-M researchers show the latter: students evaluate their instructors mostly according to quality.

"This suggests that a teacher may overcome a bad first impression by providing good instruction," said Preeti Samudra, one of the study's lead authors and a doctoral student in psychology. "Conversely, making a good first impression on students is only the beginning of the work of being an effective instructor."

The researchers set up an experiment in which subjects watched a series of video lectures. Each participant watched one of two introductory videos of an instructor, who either made a good first impression, or a bad one (by seeming disinterested, disorganized, monotone). The subject watched a second video of a lesson by the same teacher, which was designed as either a high- or low-quality lecture.

In the case of the good lecture, the professor spoke confidently and authoritatively on the topic; for the bad lecture, the professor would stumble on information and forget where he or she was in the slides. At the end, the subject was quizzed on the material covered by the lecture and was asked standard teacher evaluation questions. In addition, they rated the instructor on a variety of traits, such as confidence, honesty, professionalism and likeability.

The researchers found that instructional quality had a strong effect on both actual learning and teacher evaluations. Although there was a small measurable effect of a student's first impression on teacher evaluations regardless of subsequent lesson quality, that lesson quality was a much more significant factor in the evaluations overall.

This is good news for quality instructors who are nervous on the first day of class—just as long as they can deliver quality instruction throughout the rest of the term.

Samudra collaborated on the study, which appears in the Journal of Educational Measurement, with graduate student Inah Min and professors Kai Schnabel Cortina and Kevin Miller.