Auto Marking Get It Wrong

Auto Marking Get It Wrong

by Shin Hiorie -
Number of replies: 8

Hi Good Day All,

This is 1st time I have encounter this problem since 2011.

The moodle system mark the student answer wrongly.
The student picked the correct answer but the system mark it wrong

answerrightmarkaswrong

The student picked the right answer and the system marked it correct but the system remark the answer with wrong ico.

answerrightremarkaswrong


My checked :

1. Image 1 - the question 'Correct Answer' is True option

2. image 2 - the question 'Correct Answer' is False option

My action to fix the problem :

I've regrade the selected student attempt, but the result is the same.


Any comment on this problem ? How to rectify this ? I'm using moodle v3.3

Tq

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In reply to Shin Hiorie

Re: Auto Marking Get It Wrong

by Tim Hunt -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers
My guess was that the question had been edited after it was attempted, to change which answer was correct.

However, if that was a case, regrading would fix it, and you say that did not work. Are you really sure that you regraded the quiz?
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In reply to Tim Hunt

Re: Auto Marking Get It Wrong

by Shin Hiorie -
Hi Tim,

At first as this error was never happened before .. im actually thinking the Instuctor do some mistake in quiz setting or do some change after the attempt.

Might be the correct answer differ during and after. I also thinking that somehow there are duplicate question (same questions) in the question bank randomly set but correct answer was set differently.

But i've checked both theories ... it proof me wrong.
The question refer to same question and no changes made to the question correct answer.

And when i regrade still the system mark it wrong.
I only regraded one of the student.

Actually how we noticed this problem is when a student make a complaint. The student just after the attempt compare with his friend. Then they noticed although their answer was the same, one marked as true the other marked as false.

Tq

Tq
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In reply to Shin Hiorie

Re: Auto Marking Get It Wrong

by Tim Hunt -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers
The output of this DB query might explain what was happening behind the scenes? https://docs.moodle.org/dev/Overview_of_the_Moodle_question_engine#Detailed_data_about_an_attempt

It is really had to think what could be causing this. I suppose it could be a caching problem. Under Admin -> Plugins caching -> cache configuration, where is the Question definition cache set to be stored? (And does your setup have more than one web server?)
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In reply to Tim Hunt

Re: Auto Marking Get It Wrong

by Shin Hiorie -
OK Tim,

I think your assumption is correct.
I do the regrading on a single student by direct pointing to a server instead of through LB

Thru LB regrading will get in wrong ( 33 is not correct as I review detail attempts )
lb


While direct point get it right ( 37 is correct )
direct

However the HA setup is not new, but we did some minor adjustment recently.

Dear Tim,

Can we have the /data/cache and /data/localcache  and /data/temp reside on individual server ?
We are using tmpfs setup for that 3 datadir on each apps server to improve the speed.

Tq

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In reply to Shin Hiorie

Re: Auto Marking Get It Wrong

by Shin Hiorie -
OK TIm,

Got the answer ... only localcache can be local. Other 2 must be shared.

Can /data/cache and /data/temp set to memcached ? If yes how ?

Tq
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In reply to Shin Hiorie

Re: Auto Marking Get It Wrong

by Tim Hunt -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers
Well done for working it out. (The reason you can't have the question definition cache on local disc is that when you edit a question, it needs to be cleared from the cache, and if the cache is local, it will only be cleared on the one server that processed the edit request. Other servers go on seeing the old question.)

Caching docs are here: https://docs.moodle.org/en/Caching. Redis is typically a better choice than memecache for Moodle.
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