Once the first assignment has been handed in, we usually discover the first plagiarism cases of the term -- an occurrence as inevitable as the swallows returning to Capistrano, or the buzzards to Hinckley Ridge.
Most of the markers don't actually make a point of looking for plagiarism -- there may be a few energetic ones that suspect all students of trying to pull a fast one, but most of them are just plodding through what is a dreary and thankless task, when something strikes them as very familiar. They plow through their pile, and unearth another paper, hold the two side by side, and discover that the similarities appear more than coincidental.
I used to get angry at classes when this happened. Not any more. It's not worth the emotional effort. I am mostly annoyed, if it happens in my section, because I have to give up more of my time -- call the students in for an explanation, and listen to their lame excuses. Just once I would like to hear one say, "Yeah, I copied my friend's work. I left it too long and didn't have the time to do it myself. It was stupid." Instead, I hear things like "We talked together, but we didn't copy. I swear. I've never been accused of anything like this before." I usually reply, "Everyone says that."
Sometimes that last part of their statement is proved wrong, when we report the incident to the Associate Dean for Undergraduate Affairs, as we are required to do, and an earlier offence turns up in their files. Sometimes the first part is proved wrong, at least in my eyes, by identical wording extending over a page or two. It doesn't matter what the evidence is. I get this speech even in the most blatant of cases.
If the case is pretty marginal, or if there is a reason for the similarity, we may let people go with a warning. Sometimes, people copy wording out of the textbook as a sort of "template" for an answer. If two people do this, it can look like cheating. This is still plagiarism, but it's of a weaker sort, hence the warning. (Copying out of another text, or a Web page, is not a weaker sort.)
The penalty is familiar to anyone who's ever taken a CS course, because it is the same for all of our courses: negative 100% of the value of the assignment. There's a formal appeal process that goes on over my head, and if a student opts for this, I gather up all the photocopied evidence and forward it to the Associate Dean, which ends my involvement.
When I had a tutor who made a point of searching out plagiarism, we got numbers like this: twelve on the second assignment (I expressed alarm to the other instructor at that time, and he calmly replied, "We had twenty on one assignment last term"), sixteen on the third, twelve on the fourth. This was with a marking scheme that attached very little penalty to not completing assignments; my co-instructor predicted that it would not deter plagiarism. For some students, it is a way of life already.
Once I had the teaching staff of a course I wasn't teaching (but had taught) also notify me of plagiarism, since they reused one of my questions without sufficiently disguising it, and fifteen students reproduced my model solution (no longer available except from former students), including some typographical errors I had made. Publishers of maps often include small errors (eg towns that don't exist) in order to catch those who violate their copyrights; I wonder if we should make a point of this.
I lump plagiarism in with cramming for exams, complaining about half-marks taken off in assignments, and looking for bird courses as a sign that someone is thinking more about the number they get assigned at the end of the course than the real point of the course, which is the knowledge and skills acquired. Sure, marks are important if you're trying to keep a scholarship or maintain a continuation average, but these actions betray a lack of faith in the process. If it isn't as blatant as "The mark/credit/diploma is the only important thing, all the rest is just meaningless hoops to jump through," it's something like "Sure I didn't do this assignment, but I'll catch up and learn it by the time of the final," or "I don't see the point of this stuff, I'll never have to do this in a job." They're the same sort of thoughts, differing only in degree.
It's a slippery slope. Enough of this, and when -- if -- that rolled-up scroll gets placed in your hand as you walk across a stage, it will turn to ashes before you reach the other side. --PR
(Adapted from blog postings made October 14 and November 29, 2003.)