I think catching cheaters and plagiarizers can be fairly difficult, yet I catch a couple every year.
We are beginning to experiment with on-line courses. At this point we have no way to determine who is at the other end of the computer. The idea of a camera that periodically photographs the student is interesting, but it seems it would have to take the photo often and randomly. Even then, how do you know the photo is the correct person if you've never met the person? Sometimes the on-line student is a current student, so we know the student and have a photograph of them from when he/she got the student ID. But we will take tuition and give credit for an on-line course to someone who has never set foot on campus. It could be a total ghost, even if we took random photos.
One reason I can catch cheaters on campus is because Bluffton is small, and I am typically dealing with class sizes of 10 to 25. Since some of their work is done in class (such as essay questions on exams), I get to know how well each student writes. Then, when I am grading out-of-class work and the student miraculously writes much better, I get suspicious and begin to watch for cheating and plagiarism. Eventually I get them, usually for plagiarism from another student or from on-line sources. I might be suspicious for a few weeks before I get them. That means they have probably cheated on several assignments before I catch them, but when I do catch them the sanction can be failure of the course, and that's typically what I do.
If I were dealing with hundreds of students (or probably even 50) I don't know how I would recognize suspect work and then have the time to determine the source. Therefore, it seems to me that cheating might be easiest to do on-line, a little less easy to do in person in large schools, and even less easy to do in person at small schools. But even at small schools we have faculty who pretty much don't care. Their attitude is that cheaters are only hurting themselves. To some extent that is true, but not totally true, so I spend a fair amount of time trying to get an iron-clad case against someone I think is cheating. It's rarely easy unless the student is quite ignorant of how to pull it off.
Michael D. Edmiston, Ph.D.
Professor of Chemistry and Physics
Chair, Division of Natural and Applied Sciences
Bluffton University
Bluffton, OH 45817
(419)-358-3270
edmiston@bluffton.edu