The typo at the root of Harvard's cheating scandal

Also, even if the exam was "unrelated to the lectures", tough luck; they are paying a lot for a degree, on the understanding that the school makes the rules. If the school is being unfair, the correct response is not to cheat; it's to stop placing so much weight on a degree that really doesn't mean much.

Finally, your suggested analogy between frivolous patents and a supposedely unfair exam is nonsense. The correct analogy would be between a business that ignores a patent because it is convinced the patent is unfounded and would not stand up to a court challenge, and an employer that ignores a C in Government from Harvard (for a job applicant who took the hit on an unfair exam rather than cheat) because it knows Harvard's grades are no longer an accurate reflection of a person's job potential.

  Do people find that surprising?

Was collaboration permitted/encouraged on all assessment? In a lot of the group work at my school there tended to be some people who contributed nothing but complaints about their hangover - but who got good grades on the back of the group. I would have thought more group work would exacerbate this problem; do you think that was the case?

I had at I think one take-home exam at MIT during my time there (1991-1995) and we were explicitly allowed (and encouraged) to collaborate, so long as we gave credit to the person we collaborated with. During one of the other HN Harvard-cheating-scandal threads, another poster mentioned that a take-home exam s/he had at MIT specifically forbid collaboration.

As opposed to?

Seriously the exams should test your knowledge and application of elements from the whole range of the course material. Giving that as a reason why you can take the exam home and [have someone else] do it sounds entirely absurd to me.

Then it isn't really the same program if the changes are fundamentally different, so in essence, it isn't direct copying anymore. But changing another person's program in non-superficial ways is often as difficult as just solving the problem from scratch.

Cheating is also harder to detect in introductory classes because there are often few good ways to implement the algorithm in the first place (say, factorial, or pre-order traversal of a binary tree). Consequently, these tools tend to work better in larger projects, such as in an operating systems class.

> rename all the variables, and always use the same variables for your loops (x,y,z or i,k,l for example) between assignments and it'd be hard to detect.

It turns out this is trivial to detect; see MOSS [1] for an example of the type of analysis that is done on programs.

However, more often than not, cheating is detected by teaching assistants simply by hand ("Hmm, this submission looks familiar"), but instructors pretend that there is some sophisticated cheat-finding system to scare off students. Usually typos are dead give-aways, especially when two students have the same typo in the same comment at the same identical spot. In my academic misconduct cases, students were most often identified through spelling and grammar errors.

I imagine that there exist many more instances of cheating than instructors catch, and that we really only get the low-hanging fruit (and frankly, my job isn't to be the cheating police, so I don't go out of my way to find it). But catching the most obvious cases and having a severe punishment as a deterrence is often enough. ("If you cheat, you likely won't get caught, but if you do, goodbye -- it's automatic failure at minimum, and possibly suspension or expulsion.")

[1] http://theory.stanford.edu/~aiken/moss/ and the actual research paper http://theory.stanford.edu/~aiken/publications/papers/sigmod...

Also keep in mind that if you're grading 50 people like I was, you won't remember what variables the students used between assignments. The stuff they would do to throw me off the trail wouldn't help much at all.

If I found a student had copied from a neighbor or whatever, I'd ask them both what had happened. It was uncommon that they would deny it. I'd tell the professor and mark the assignment a zero. After that, it was between the students and the professor.

Try it yourself, write a small program, perhaps a script to read a CSV of numbers and do a pivot table or something, then copy it and use whatever technique you like to hide the copying. Now read them back to back. Give no more than 1 minute to each (since they both compile and pass tests). You'll spot the copying immediately.

Disclaimer: I did TA work for undergraduate stuff; typically for students in liberal arts and sciences just trying to get through their comp-sci requirements.