students editing output

[David Parter]

> Stephen Hartley (hartley%uvm at csnet-relay) worries (and, I believe, not
> without cause):

> > ... students ... tailor[ing] their output with an editor to be more
> > correct. What do other people do?

David Luner (luner at wisc-ai) writes:
> I make a point to tell my classes that the faking of results is a serious
> breach of trust and will be dealt with severely. I emphasize that the programs
> I ask them to write I have seen in many versions, both correct and incorrect
> that they should not expect an error to slip by. [The truth of this depends
> on exactly what language and what programs they're doing, but they don't 
> know that.]
> 					/David

the problem is to prevent such cheating. It is very hard to do, and 
intimidating the students is not enough.  The only thing i can think of
off hand is perhaps writing a special version of script that puts the 
script file in a secure directory, marked as to which student ran it,
what data set was run and when.

In addition, provisions have to be made for a bad run (typos, anyone?)
so if the student ran it again for the same test data, it should
overwrite the previous version, up until the time when no more 
programs are accepted.  And then whatever is in that directory is what 
gets graded.

Of course, if the instructor suspects cheating, it is easier to prove in
CS than in other fields.... just demand a demo. Or diff the files, check
the creation dates or even the backup tapes from a previous semester,
depending upon the exact problem (all of the above have been done).

i work in the Systems Lab here at Wisconsin, and have helped some
faculty with this in the past. As a student in the department, i am
particularly sensitive to this problem. I wish it would go away.

david
-- 
david parter
UWisc Systems Lab

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