[LON-CAPA-users] Action items page
Wed, 21 Sep 2005 08:47:33 -0400
On Sep 21, 2005, at 2:12 AM, Lars Jensen wrote:
> (2)Once, I checked off the "Reset Count" box, that seemed to remove
> the problem for a while, but it popped back into the list later? Why?
Because the criterion set still applies, even after another batch of
students went through.
> (3) Problems seem to pile up in a long list... Is there no other
> way to shorten the list than checking off each problem
> individually, and resetting the counter? It seems like a "check
> all" button on this page might be a good idea.
Yep, same here initially. The default criteria for the warnings are
set to be pretty sensitive. There is a button in the heading of that
column where you can adjust the warning levels. I have set them to
degree of difficulty greater than 0.8, at least 5 tries, and at least
three students meeting the criterion before issuing the warning. Now
it's useful for a 220 student course. I think the default criteria
were designed to also match smaller courses, but I am afraid we were
Remaining bug: essay problems still always issue warnings.
> (4) What is the "degree of difficulty" of a problem?
I don't remember the formula, but it involves number of tries till
students succeed. Works pretty well:
0: everybody gets it (probably a broken problem, always right on the
< 0.3: easy problem
0.3<x<0.7: good problem
> 0.7: hard problem
1: nobody ever gets it (probably broken problem)
I analyzed the quality of ensuing online student discussions as a
function of degree of difficulty and actually got significant
results. At least when it comes to students discussing concepts with
each other (rather than expressing frustration, etc), anything beyond
0.7 only increases the pain, not the gain.