## Wrong answers and wrong questions

This post is a sequel to the previous: I have done some thinking concerning the question in my yesterday’s exam – it’s not just tricky, it’s conceptually wrong. Because of a mere typo in the problem statement (one minus omitted), the problem had no reasonable solution whatsoever. Now, the question is how to grade such an exam?

1. If you give all students maximum points on the problem, then all will pass – exam loses its sense.

2. If you decide not to grade this problem, and double the points on the second problem, people concentrating on the wrong problem lose the chance to pass – it is clearly not fair.

3. Give full marks to students getting as far as they can with the wrong problem statement, give full marks to students who notice the error and try to correct it and give full marks to students who obtain the correct solution using the wrong problem statement (people trying to tweak the intuitive solution – based on the fact that the question has a trick hidden, as noted in my previous post – into the formal solution which by default does not make sense).

I would vote for 3. Now, there is one more question concerning grading exams I would like to ask:

How to grade an exam in which the student made an error while copying it in his/her exam notebook? It may be that (s)he either:

a) trivialized the problem that way

b) made the problem more complicated

c) problem difficulty remained the same

If a) is the case, most TAs simply grade it with a zero, but what about b) and c)? Again, there are three options – zero it, give full marks for a correct solution of the incorrect problem, or give almost full marks for a correct solution. Last two options mean more hard work for the TA, since (s)he has to go through a new problem and check the solution, but it is much more fair than the first option.

I stated my opinions above, because I felt the need to write it down – if anyone ever walks in this dark corner of World Wide Web and has an opinion about these questions – the “Leave a comment” link is somewhere on the left.