I think that you make an important point. Not counting detected cheaters in course evaluations seems like a good policy. This is especially true because stude

I think that you make an important point. Not counting detected cheaters in course evaluations seems like a good policy. This is especially true because student evaluations have been shown in a number of cases to be very highly correlated with the student's expected grade. However, I still agree with Panos' diagnosis that his student evaluations went down in response to detecting cheating. He presumably has data from hundreds of students over years of classes. The primary difference between this year and past years was almost certainly his detection of cheaters. While removing cheaters from the evaluation pool may mitigate the problem a little, I find it pretty plausible that evaluations went down because of some cheating-detection related phenomenon, like the more adversarial atmosphere, his own feelings about the cheaters, or students feeling attacked or accused.