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First of all, thank you Chofer for the good faith effort to answer this! However, looking at the document you referenced ( https://community.canvaslms.com/t5/Instructor-Guide/Once-I-publish-a-quiz-what-kinds-of-quiz-statistics-are/ta-p/659 ) I cannot reproduce the discrimination index using the calculation methods shown and the CSV data. As noted by Vastib, what the quiz statistics screen seems to be showing is the point biserial. There are two sources of information on quiz statistics: Quiz summary screen (obtained by clicking on "Quiz Statistics" when in a quiz) - this includes a calculated discrimination index Item analysis CSV (obtained by clicking on Item Analysis link, when in Quiz Statistics) - this does not list a calculated discrimination index  For me, it would be great to be able to calculate, or otherwise download discrimination indices, but they are not listed in the item analysis. [However, what is in the item analysis CSV (of which more later) is the "Point Biserial of Correct".] Looking at the "Once I publish a quiz, what kinds of quiz statistics are available?" link from Chofer, it would seem to be trivial to reproduce the DIs! I quote from the link: "It (the discrimination index) divides students into three groups based on their score on the whole quiz: the top 27%, the middle 46%, and the bottom 27%. The number of correct answers from the bottom group is subtracted from the number of correct answers in the top group, then the total is divided by the size of the group." But when you use the data in the item analysis CSV (source 2), the calculated discrimination index is not the same as the one displayed on the quiz statistics screen (source 1). Specifically, (using the CSV column titles) I'm calculating (Correct Top Student Count-Correct Bottom Student Count)/((Top Student Count+Bottom Student Count)/2) [Average group size is used because the bottom student count is different (slightly less) than the top student count in my CSV]. The calculated numbers are not the same as the displayed discrimination index in nearly all cases. Sometimes they are close (for 7 out of 37 questions in my quiz, the difference is less than +/-0.02). The average difference is 0.08 (23% of the displayed DIs). However, the displayed discriminant index from source 1 (screen) is identical to the Point biserial of correct column in source 2 (the CSV). So you can use that column to download the displayed DIs that you see on the screen.  Some discussion of the strengths of the point biserial are shown here -- Use point-biserial to discriminate high and low performers | GradeHub       ... View more