Re: [seul-edu] tutor-web (long)

[Roger Dingledine <arma@mit.edu>]

Most of this isn't my area of expertise, so I'll leave most of the
answers here to actual teachers. :)

On Thu, Dec 28, 2000 at 05:15:48PM +0000, Gunnar Stefansson wrote:
> A unified system to replace my PowerPoint presentations, class
> handouts in Word or TeX, student quizzes, homework and mid-terms and a
> few other things.

My first thought is that there are already projects out there working
towards this sort of thing. None of them has quite the focus or intent
that you do, but that doesn't mean you can't reuse their work. Something
in the back of my mind keeps saying 'zope', but I have no idea why. (Any
of the zope advocates here want to expand on this?)
 
> The quiz: Each page should have a "Q"uiz button, intended to whip up a
> question on the topic.  Now, since these should be *used* rather than
> just be for fun, two students sitting beside each other should not get
> the exact same questions.  Three methods should be implemented (at

Because you're worried about collaboration?

> Requirements: A student is required to obtain 75% (7.5 out of 10 or
> GPA of 3, if you like) in order to pass a course on the tutor-web.
> Note that this is not like a paper-test but rather like requiring a
> student to hand in 75% of all homework assignments.  The number needs
> to be quite high given the possible repeats, so maybe it should be
> 90% -- but certainly not 50%.  NB:  Any grading scheme needs to be
> tested against someone using repeated guesses, i.e. how long would it
> take a guesser to pass a course.

It seems to me that you've got your threat model wrong. You're worried
about trying to 'enforce' that people play fair. I don't think that will
work (certainly not easily). You talk above of modelling it to determine
how easy it is to pass the class based on randomly selecting answers;
but that's not the way I would attack if I were trying to pass the class
without learning the material. For nearly all grading schemes you propose,
I could write a script to gather answers (either by guessing until I
knew all the questions and then getting 10 right as you describe above,
or by creating multiple anonymous accounts until I knew all the questions,
etc) and automate the task of passing a class. If I am determined enough,
I will beat your system.

There has to be some amount of trust involved. You should consider what
your goals really are and what tradeoffs you're willing to make (eg in
convenience) to achieve them.

I'd be happy to talk to you more about your grading scheme as it gets
closer to being needed. I'm not so experienced with this teaching thing
(I've only taught two terms of one class each), but security is my
specialty. (And come to think of it, I've taken classes for 17 years.
I must have *some* perspective by now on how they should work. :)

> Funding:  Currently out of my pocket.  Depending on response, we may
> have to move to other computing equipment, allow an advertisement in a 
> bottom corner of each page, or whatever.
 
Just work on making the system work and be useful. Once it's useful,
I'll take care of making sure hosting happens.

(Rule of thumb: you should *never* let "i don't have a machine to run it
from" stop you from building a service which is useful to the community.
If it's useful, I'll take care of finding it a home.)

--Roger