WeBWorK Problems

Eliminating guessing on matching problems

Re: Eliminating guessing on matching problems

by Paul Pearson -
Number of replies: 0

There is a grader that allows you to award different amounts of credit depending on how many parts students get correct. This is explained in Example 1 on the wiki page


Basically, you need to load the PGgraders.pl macro, and use the "custom problem grader fluid":

----- begin PG code -------------


$ENV{'grader_numright'} = [2,5,7,8];
$ENV{'grader_scores'} = [0.1,0.6,0.8,1];
$ENV{'grader_message'} = "You can earn " .
"10% partial credit for 2 - 4 correct answers, " .
"60% partial credit for 5 - 6 correct answers, and " .
"80% partial credit for 7 correct answers.";

$showPartialCorrectAnswers = 0;

-------- end PG code --------------------

Due to a recent change in "answer keys" (the way that answer blanks are labeled in the html input form), to get everything working you must use the most recent version of PGgraders.pl, available via SVN from


If you are unable to update this file on your server, you could put PGgraders.pl in the /templates/macros directory of your course.

Good luck!