Monday, November 12, 2007

Exam II results

So the exam results are in (except for a couple of you that had a reason to make it up late). You will get your exams back tomorrow.

The raw average was 70.7%, with a standard deviation of 18.5. Not to bad, but the spread was too high. I scaled the overall result to have an average of 80%, with a standard deviation of 12.5%, which makes the distribution more comparable to the last exam and a bit more fair I think. Here is what that looks like:

If we look at the average score by question, and the number that chose to respond (recall you had to pick 8 of 12 questions), it is easy to see which questions you perceived as being more difficult. Moreover, the second plot shows that your instincts were, as a whole, correct: questions perceived as more difficult (fewer people trying them) had a lower score on average.


Apparently, questions 6 and 7 were just mean. Maybe question 3 as well, but that was taken almost verbatim from the homework.

Anyway: you all did better than you think. Below is the breakdown by letter grade. Full exam solutions should be out by week's end.

A: 12
B: 11
C: 14
D: 5
F: 4

Exam II

So. I've been out of town this whole time, and have not been so responsive.

I have nearly finished grading/analyzing exam II, and I will post more information later today.

I can say this already though: Relax. I am not going to fail inordinate numbers of you. The exam will be scaled if necessary, and no one is going to radically change their grade as a result of the exam. It Will be Fine.