[ARCHIVED] Quiz Statistics -- Incorrect Standard Deviation

alwan
Community Novice

Canvas mixes "apples and oranges" with units on quiz statistics. It reports the mean in % units but the standard deviation in units of the number of questions in the quiz. For example, in the latest quiz I gave (11 questions), Canvas reported 83% for the mean and 2.12 for the standard deviation. Looking at the spread of the data, it wasn't possible for the standard deviation to be 2.12. I then realized that it was computed based on the points correct out of 11. This is deceiving. If reporting a mean in %, then the standard deviation should be in % units which for my case would be as standard deviation of around 19.

To get the standard deviation so one can have apples to apples comparison, one has to take Canvas' reported standard deviation and multiply it by (100/# of questions), unnecessary pain.

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