For the calculation of the guess correction penalty, it currently only considers combinations with the number of correct options.
I.e., with 4 options, 2 correct, the calculation only considers the combinations with 2 options selected (=6 combinations -> -2.0 deduction) , while students may also select 0,1,3 and 4 options (=16 combinations in total -> -0.666.. deduction).

The probability of some of the possible combinations to be selected is debatable (e.g. 0 and all options). In calculating the guess correction penalty, we will treat each combination, including those with zero or all options selected, as equally probable for now.

Submitted by Elmer van Chastelet on 2 October 2024 at 14:27