WeBWorK Problems

compound problems

compound problems

by Kenneth Appel -
Number of replies: 1
Davide,
I understand that you plan to modify compoundProblems.pl and hope that
other users and I could make suggestions based on how we plan to write
compound problems. Since the current version was based on the needs of
some users, it might even be desirable to have more than one version when
there are conflicting needs. I realize that it is unlikely that you will be able
to satisfy all wish-lists, but if users provide such lists I hope that it will help
you in designing a product with features that make it more desirable for
many users.

I am now writing problems at the middle school level and use them for
two purposes. One is to introduce students to enrichment material and the other is to provide careful re-introduction to critical material that the users
have not understood. In each case, it is important that the student not be
able to proceed past the section he or she is working on without answering
the questions correctly. But I tend to put material in each section with its
use in later sections in mind and would like the student to be able to refer
back to prior work easily (especially if the compound problem is not finished
in a single sitting).

Ideally, for me, the compound problems should have the following
properties.

1. As is currently the case, students should have no access to the n-th portion
of the problem until he or she has successfully completed all prior portions.

2. The students who are working on the n-th portion should have easy access
to their work on all of the first n portions. (Among other things, this makes
it unnecessary to repeat caveats and the the like). In the best possible world
students should be able to move easily from any portion to any other portions.

3. (less important but desirable to me) The problem writer should be able
to name the parts to make it easier for students to see which prior part is
likely to have the information that they want.

In the current compoundProblem.pl there is at least one undesirable piecesthat I
am sure you already know about, but I will list it just for completeness.
Currently, in order to move to the n-th part upon completion of the n-1-st
the student must submit correct answers but these correct answers do not
allow the student to go on. They just allow the student to get a question
asking whether he or she wants to go on. The student must resubmit answers
along with an affirmative answer to that question in order to go on. If, at
the time answers are submitted a student is allowed to answer the question
of the form: "If this work is correct would you like to proceed to the next
part?", the double step could be eliminated.

Thanks again for your work in writing the current version. I believe that
it is one of the most useful innovations in making WeBWorK a teaching system
in addition its original purpose as a problem presentation and grading system
Ken

In reply to Kenneth Appel

Re: compound problems

by Davide Cervone -
As you mention, 1 is already true.

Your 2 is certainly planned for the future version. The author will have control over whether students can go back or not, whether previous parts will allow answers to be resubmitted, and whether parts "accumulate" (so they all show at once) or only the active part is shown.

Your 3 is a good suggestion, and I will add it to my list or requests.

See http://webwork.maa.org/moodle/mod/wiki/view.php?id=164 for more about the compound problem plans.

Your comment about going on to the next part is certainly one that I have heard before, but because of he way that WeBWorK works internally, it is not possible to do as you request (at least not without major changes to PG). The reason is that the text of the problem is generated BEFORE the students answers are checked. Indeed, as the problem is processed, the text is created, and at the same time, the correct answers are determined, and the answer checkers are assigned to them. All of that has to be done before the student answers can be checked. Then the answers are checked and the grader is called to determine the final score. Finally, the answer result table is placed at the top of the page.

So the point when we know whether the student's answers are correct or not doesn't occur until after the text of the page is created. The text that shows up must be the text that goes with the answers that are being checked (not the answers for the next part). This is the reason for the second submit. I understand that it is undesirable, but I don't see any practical way around it within WeBWorK's current problem framework.

See http://webwork.maa.org/moodle/mod/forum/discuss.php?d=5834 for more details.

Davide