

Using IRT Instead of Traditional Grading to Assess Students - achompas
http://www.knewton.com/tech/blog/2012/06/understanding-student-performance-with-item-response-theory/

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tzs
Could a bayesian approach work for this kind of thing? You treat each question
as a separate test, and use it to update your believe in the hypothesis that
the student is an A student. Do this for all questions, to get a final degree
of believe that the student is an A student.

Do similar for the hypothesis that the student is a B student, and so on for
C, D, and F. Then give them the grade that ends up with the highest degree of
belief.

Yes, I didn't say anything about how to assign your initial degree of belief.

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achompas
You've got the right idea--there's lots of recent literature treating the
typical IRT problem as a Bayesian inference problem. Some of the references
listed at the bottom of the article (especially the Kim one) provide great
literature surveys.

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jon6
I didn't really follow the math here but is a simpler solution just to give
different questions different points?

1\. What is ...? (Worth 1 point) 2\. What is ...? (Worth 2 points)

It looks like IRT is for somehow determining the difficulty of a test given
the answers of students.

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Semaphor
Yeah, the article seems to start at a weird point. An algorithm to find out
how many points a given question is worth might be better than having the
teacher just decide what is worth how much. Or it might be worth.

But what kind of stupid school system would grade math per question instead of
per difficulty?

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achompas
I'd agree, if finding such an algorithm was easy! :)

