Grading deviations

Grading deviations

by Stephan L -
Number of replies: 1

Hi!

I'm not sure if this problem is the same as the previous topics in here (grading tree option isn't even present inside of the assessment form), but recently I discovered some score deviations, which should not happen.  

The deviation occures like in the following example:

The complete achievable score is 50 points and is separated into 5 aspects with:

  • 1. Aspect: 20 Points
  • 2. Aspect: 10 Points
  • 3. Aspect: 10 Points
  • 4. Aspect: 5 Points
  • 5. Aspect: 5 Points

One peer assessed the submission with 19/20, 10/10, 10/10, 4/5 and 3/5, which would result into 46 points when summed up by hand. However moodle is calculating a score of 44 points or 43,50 if calculated using floating points. Inside of the database the grading for this particular assessment set is 87%. 

How is this possible? I checked every setting (which should be on default anyway) but didn't find why the points are not summed correctly... 

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In reply to Stephan L

Re: Grading deviations

by David Mudrák -
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Hi Stephan.

The reason is that Workshop calculates the final grade differently as described at https://docs.moodle.org/en/Workshop_grading_strategies#Accumulative_grading_strategy Please refer to the example provided there which should explain how the final grade was computed.

I can understand that it would be more intuitive to use "natural" calculation like you described, without the need to have weights involved. For legacy reasons and backwards compatibility with how Workshop used to behave in Moodle 1.x, it was implemented this way.

To emulate your expected outcome, you would need to set the weight of aspects 4 and 5 to weight 1; aspects 2 and 3 to weight 2; and aspect 1 to have weight 4. Then the final grade would be 46.

Hope this explains.

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