[LON-CAPA-users] Partial Credit for a Problem?

[Todd Ruskell]

We are developing some problems for which the instructor wants to award
"partial credit" in a situation like this.  Allow a single attempt.  If
the answer is with 2% of the "correct" answer, full credit, within 10%
of the correct answer, give 90%, and so on.  

We're wondering about the best way to do this.  I see at least two
possibilities:

(1) Each problem part appears to have its own partial_credit_factor
parameter.  Is there a way inside the script of a problem to do some
calculations and assign a value to this parameter?  If so, how? At
http://s10.lite.msu.edu/res/msu/albertel/test/ext_examples.problem
I see a reference to "user.resource.resource.<partid>.awarded"
How is this related to the partial_credit_factor parameter?  Are they in
fact the same?

Anyway, I'm guessing I could use something like 
&EXT(user.resource.resource.<partid>.awarded) = $PCF_Desired;

But can I be sure this overrides other values?

This method would have the advantage of being able to instantly tell the
student his grade on the problem.

(2) Use the spreadsheet.  The spreadsheet is mostly my friend these
days, but because it is so slow, I'm thinking doing this calculation in
the problem itself would be more efficient.  With the spreadsheet mode,
a student would also *have* to do a grade check to determine the amount
of credit awarded.

(3) Any other better ideas?

Thanks,

Todd


-- 
Dr. Todd Ruskell			
Lecturer, Department of Physics		Office: Meyer Hall 326
Colorado School of Mines		Phone: 303-384-2080
1523 Illinois Street			Fax: 303-273-3919
Golden, CO 80401