Expected value of multiple choice exercise

25 Views Asked by At

I hope this question is not too off-topic but I am wondering why the multiple choice exercise (just "Yes" or "No" answers) in our exam is graded as follows:

Every correct answer gives $3$ points, every wrong answers gives $0$ points and if you don't answer you receive $1.5$ points.

Have you any idea why someone would use this strange grading scheme? In my opinion this grading scheme would be a strong advantage, in terms of expected value, to students who didn't learn. Or am I missing something?

Why not just give negative points for wrong answers and $0$ points for not answering? This would be less advantageous for students who didn't learn.