Grading miscalculation

[Xochipani]

My two exams represent 20% of the final grade; each counts 10%. When calculating the grade, I notice some inconsistencies. For instance, if the grade of one exam is zero and the grade of a student before entering that grade is 66, it goes down four points to 62, not 56, which I would expect it to be the case. Do you have any ideas about why that is happening or how to solve it?

[stimme · Accepted solution]

@Xochipani When not every assignment has a score, Canvas calculates a final percentage using the scores that are available and the weights of the assignment groups to which they belong. Canvas excludes assignments without scores from the summations of points earned and points possible for their assignment groups. In the example you propose (for a student who gets 0% on an exam worth 10% of final grade weight, the student's final percentage should decrease by 10 points), Canvas would need to include unscored assignments with the assumption the student will earn 100% of the points possible.

It's not the only possibility, but one simple scenario where a student could have 66% with all assignments except one exam scored and then have 62% after earning 0% on that exam is:

Assignment Group 1 is Homework, weight 80%. The student has earned 290/400 (72.5%). When the other assignment groups have some scored assignment, this group contributes 0.58 (0.725 * 0.8) to the total.

Assignment Group 2: Exams, weight 20%. The student earned 40/100 on exam 1, 0/100 on exam 2. With the score for exam 1 only, this group contributes 0.08 (0.4 * 0.2) to the total, which is 0.66. With scores for both exams, this group contributes 0.04 (0.2 * 0.2) to the total, so that the student has 0.62.

I hope this makes sense!