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WeBWorK says student's answer is correct but gives 0 points and didn't save answer

WeBWorK says student's answer is correct but gives 0 points and didn't save answer

by Sarah Weatherman -
Number of replies: 8

Conflicting correctness information on student's answer

The student's Entered answer matches the Answer Preview, and the Result is correct, but the student got 0 points for this problem, and it is marked as incorrect in the list of Problems on the left.

I looked at the student's responses in the problem set, and I could see the answers they entered for the other problems, but not this one. The answer for this one is blank, though there is a timestamp for when the answer was entered.

How can this be fixed? What could cause this?

Thanks for any help, and let me know if there is any more information that could be useful. I'm pretty new to WeBWorK and don't use it myself, so I have limited familiarity with it outside of creating courses. 


In reply to Sarah Weatherman

Re: WeBWorK says student's answer is correct but gives 0 points and didn't save answer

by Alex Jordan -

Note in the screen shot how there is a "Check Answers" button but no "Submit Answers" button. This most likely means that it is past the homework set's close date. It is past the the time when students can earn credit. But they can still type in answers to see if they are right or not using "Check Answers".

In reply to Alex Jordan

Re: WeBWorK says student's answer is correct but gives 0 points and didn't save answer

by Sarah Weatherman -

But other students were able to submit answers after this student, and this student was able to submit answers to the other problems in this problem set after this. Is it possible to have a different close date for one problem in a set for one student? If so, where would one go to see/edit it?

In reply to Sarah Weatherman

Re: WeBWorK says student's answer is correct but gives 0 points and didn't save answer

by Alex Jordan -

It is possible to have the close date for a set be different for one student than for other students. One way to look into that is to click Instructor Tools. Select the student, select the problem set, and click to look at the details for that student for that set.

It is not possible for one problem in a set to have a different close date than other problems.

Who generated that screen shot? If it was the student, that screen shot was generated after the problem set due date. This is evident because there is a "Check" button instead of a "Submit" button.

The student has credit for other problems. Are you sure they did not submit answers to other problems before the close date, but did not actually submit an answer for this one problem before the close date?

You can examine a log file of everything the student submitted, and when they submitted it. This log file is in the File Manager. Navigate up one level from where you start, to the course's root folder. Then there is a logs folder, and in there is an answer log file you can view. Search in that file for as follows. If the user ID were alex.jordan, and the problem set name is Homework_1, search for
alex.jordan|Homework_1
with the pipe character between them. This will jump you to see the timing details of what this student actually submitted prior to the close date.

In reply to Alex Jordan

Re: WeBWorK says student's answer is correct but gives 0 points and didn't save answer

by Sarah Weatherman -

The close date was 03/11/2021 at 11:45am and the screenshot was sent to me on 3/9. Can the students not check their answers after submitting them?

Also, in the answer log, the entries are in the format userID|ProblemSetName|QuestionNumber|what appears to be a binary number.

Does that number following the question number indicate anything? It differs on different students and questions, but I can't see any pattern.

In reply to Sarah Weatherman

Re: WeBWorK says student's answer is correct but gives 0 points and didn't save answer

by Danny Glin -
A student will see the "Check answers" button when they are no longer able to get credit for the problem.  If this happens before the due date it is most likely because the student has used all of their attempts on the problem.

Can you post a screenshot of what you see when you act as the student and click on the "Show past answers" button on that question (make sure that it is anonymized).
In reply to Danny Glin

Re: WeBWorK says student's answer is correct but gives 0 points and didn't save answer

by Sarah Weatherman -

Past answers for problem

What's confusing to me is that the first screenshot shows the values that the student entered (so the answer was not blank), but the Past Answers contains only "empty," but also has a timestamp that I think suggest the student did submit an answer and did not skip or omit the question.

In reply to Danny Glin

Re: WeBWorK says student's answer is correct but gives 0 points and didn't save answer

by Alex Jordan -
To tie the thread, I met with Sarah on a video conference and it was as Danny suspected. The instructor (who is not Sarah) has the problem set to 1 attempt. The one and only attempt was used up with a blank submission.

I showed Sarah how to use Instructor Tools to change the student's score, give additional attempts, and reopen the set for just that one student. And the instructor might consider whether they really want to limit to just one attempt.

Perhaps an empty submission should not count as an attempt. But in some rare situations, an empty string is the correct answer. So I don't know.

It is also evident that the message to the student that they only have one attempt or that they have used up all of their attempts did not come through clearly to the student. So perhaps we can do something about that for a future release.
In reply to Sarah Weatherman

Re: WeBWorK says student's answer is correct but gives 0 points and didn't save answer

by Alex Jordan -

Those 1s and 0s are "correct" and "incorrect". For example, for a problem that has three answer blanks, for a student you might see 110, meaning the first two answer blanks were assessed as correct, and the third was not.

This problem has two input fields but it appears they are tied together as part of one answer, given the results table. So I am guessing for this question, you see either a 1 or a 0 depending on the student.