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Multiple Choice Partial Credit Issue

Amie Little
Multiple Choice Partial Credit Issue
by Amie Little - Tuesday, 11 May 2021, 11:16 AM

Hello, everyone!

I have noticed that with multiple choice (multiple correct answers), it is possible for a student to choose an incorrect answer and still receive 100%.

With our grading method, we divide 100% by the number of possible answer choices to find the value of each choice. This allows students to receive credit for each choice they correctly select and correctly do not select. 

In Totara, all of the correct answer choices must add up to 100%. If students select all possible answer choices when all answer choices are not correct, they will still receive full credit since the wrong answer choices do not carry a penalty.

Use the following question as an example:

What food items are considered fruit?

A. Apples

B. Bananas

C. Carrots

D. Dates

In Totara, choices A, B, and D must each have a value of 33.3% and choice C would have a value of 0%. However, by my math, it seems that each answer should have a value of 25%.

Any advice would be greatly appreciated!

Nathan Harris
Re: Multiple Choice Partial Credit Issue
by Nathan Harris - Tuesday, 11 May 2021, 3:32 PM

Hi Amie,

In your example question you need to make Option C a negative percentage.  That way if the student selects it it will subtract from the end score and they won't gain the 100% pass score.



Amie Little
Re: Multiple Choice Partial Credit Issue
by Amie Little - Wednesday, 12 May 2021, 7:01 AM

Hi, Nathan!

Thank you so much for your suggestion! In our case, we cannot use the negative values for the wrong answer choice as this would produce inaccurate results for our grading method. 

Using the example listed in the original post above, if we put the incorrect choice at a value of -33.3%, this would correct the issue of students selecting all answer choices, but it would cause another issue if the student does not select all the answer choices. If a student selects only 1 correct answer and the 1 wrong answer, the two values would cancel each other out for the student to receive a score of 0. We also cannot use the -25% value for the incorrect choice as this would still produce an inaccurate value of points for the question (8.3%).

Any other thoughts or suggestions would be greatly appreciated! Thanks!