help interpreting the statistics associated with quizzes

help interpreting the statistics associated with quizzes

by Cydney Mullen -
Number of replies: 3

Good afternoon,

We have begun online testing using the quiz function in Moodle, version 3.4.3. I am having difficulty understanding the statistical analyses that are provided after each quiz. For instance, the statistic "discrimination index", according to my understanding, should be a number between 0 and 1.0. I am obtaining weird numbers like 25.43% and -2.60%, for instance. These numbers do not make sense to me, and if someone can provide an explanation for how I am to interpret these numbers, I would very much appreciate it. Thank you!

Cydney Mullen, PhD

Sandhills Community College

Pinehurst, NC

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In reply to Cydney Mullen

Re: help interpreting the statistics associated with quizzes

by Tim Hunt -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers

The places to start are:


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In reply to Tim Hunt

Re: help interpreting the statistics associated with quizzes

by Cydney Mullen -

Tim, I reviewed every single one of these sources. I did that before I posted my question. I was hoping that someone has some practical guidance for me in understanding the resulting statistics. We all want very much to use on line testing via Moodle, but the statistics must make sense to us in order to do so. For instance, as I said, I understand a discrimination index to be a number between -1 and +1. The numbers that Moodle give me for this particular statistic range anywhere from -2% to 24% or more (as examples.). How do these numbers relate to a number between -1 and +1?

This is just one big example. Am I expected to actually hand calculate the discrimination index and discrimation efficiency, or just learn a different way of understanding the numbers that Moodle calculates?

Can anyone provide me with any guidance, or a phone number to call for help?

Cydney Mullen, PhD, Sandhills Community College

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In reply to Cydney Mullen

Re: help interpreting the statistics associated with quizzes

by Tim Hunt -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers

I think the Descrimination index is just shown as a percentage. +1 = 100%. -1 = -100%. 24% = 0.24, etc.

Average of ratings: Useful (1)