Difference between revisions of "Gradebook calculation changes"

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(20150619 MDL-49257 Calculation of the extra credit items weights in Natural aggregation method (version 2.8 and above))
(rewording, grades template)
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'''As decided in MDL-50582 and MDL-50222 all the bug fixes in grades calculations do not apply during upgrade if they can change the existing grades.'''
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{{Grades}}
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<p class="note">Note: This page only applies to sites upgrading from Moodle 2.7 or earlier.</p>
  
During upgrade Moodle will identify which courses are affected by the bug fix and '''freeze the gradebook calculation methods''' to the previous version. The message will be displayed to the teacher and teacher must manually accept the potential changes in the grades.
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Moodle 2.8 includes a number of gradebook error fixes which can affect gradebook calculations in certain courses. As part of the upgrade process, such courses are identified and a message is displayed in the gradebook informing teachers that error fixes will result in some grades being changed. Details of these changes are provided below. The 8-digit version number is the date of the fix.
  
Below is the list of all the fixes since gradebook versioning was introduced. The 8-digit version number is the date of the fix. Your Moodle release number also contains the 8-digit number that refers to the date when this version was build. Accepting the changes will progress your "gradebook code version" from the one when it was freezed to the latest available in your current version. Please note that if you are not using the latest weekly release this page may contain the fixes that are not yet available in your Moodle.
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It is recommended that the errors are fixed by clicking the button 'Accept grade changes and fix calculation errors'. Until this is done, the message will continue to be displayed in the gradebook and it will not be possible to edit grades.
  
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=== 20150619 - Calculation of extra credit item weights when using natural aggregation ===
  
=== 20150619 MDL-49257 Calculation of the extra credit items weights in Natural aggregation method (version 2.8 and above) ===
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Two errors were fixed:
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# Overriding the weight of the extra credit item can lead to changes in other items' weights and pretty random final grades
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# The automatic weight of an extra credit item was dependent on the overrides of the normal item's weights
  
Two bugs were fixed here. First, very critical: overriding the weight of the extra credit item can lead to changes in other items' weights and pretty random final grades. Second, the automatic weight of extra credit item was dependent on the overrides of the normal item's weights (and it should not). This especially becomes noticeable for the students that have grade items excluded them from totals (for example, when they are hidden or empty). [https://tracker.moodle.org/browse/MDL-49257?focusedCommentId=358765&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-358765 Here] you can find lots of the screenshots of before/after behaviour (note that table is very wide and the horizontal scrollbar appears underneath).
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The second error was especially noticeable for students with excluded grade items (for example, when they are hidden or empty).  
  
Video with the demonstration of the first bug: http://youtu.be/-mQ1cWzNuxI
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For example, a category has two normal grade items and one extra credit item. If the maximum grades for each item are the same, the weights of the three items will be: 50%, 50% and 50%. However if the weights of the normal items are overridden to be 50% and 50%, then the weight of the extra credit item would become 0%. If the teacher overrode the weight of the first item to 80%, the second item would automatically become 20% (correct) and the extra credit would also become 20% (incorrect).
  
The simpliest example of the second bug: The category (or course) has two normal grade items and one extra credit item. If all maximum grades are the same, the weights of three items will be: 50%, 50% and 50%. However if the weights of the normal items are overridden to be 50% and 50%, the weight of the extra credit item magically became 0%. If teacher overrode weight of the first item to 80%, the second item automatically becomes 20% (correct) and the extra credit also becomes 20% (incorrect).  
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The correct behaviour (after the fix): If the weight of extra credit item is not overridden, it should be itemmaxgrade / totalmaxgrade , where totalmaxgrade does not include the extra credit item. In the example, the weight of the extra credit item should always be 50%.
  
Correct behaviour (after the fix): If the weight of extra credit item is not overridden, it should be itemmaxgrade / totalmaxgrade , where totalmaxgrade does not include extra credit item. In the example above the weight of extra credit item should always be 50%
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See MDL-49257 for further details including screenshots.

Revision as of 16:12, 24 June 2015

Note: This page only applies to sites upgrading from Moodle 2.7 or earlier.

Moodle 2.8 includes a number of gradebook error fixes which can affect gradebook calculations in certain courses. As part of the upgrade process, such courses are identified and a message is displayed in the gradebook informing teachers that error fixes will result in some grades being changed. Details of these changes are provided below. The 8-digit version number is the date of the fix.

It is recommended that the errors are fixed by clicking the button 'Accept grade changes and fix calculation errors'. Until this is done, the message will continue to be displayed in the gradebook and it will not be possible to edit grades.

20150619 - Calculation of extra credit item weights when using natural aggregation

Two errors were fixed:

  1. Overriding the weight of the extra credit item can lead to changes in other items' weights and pretty random final grades
  2. The automatic weight of an extra credit item was dependent on the overrides of the normal item's weights

The second error was especially noticeable for students with excluded grade items (for example, when they are hidden or empty).

For example, a category has two normal grade items and one extra credit item. If the maximum grades for each item are the same, the weights of the three items will be: 50%, 50% and 50%. However if the weights of the normal items are overridden to be 50% and 50%, then the weight of the extra credit item would become 0%. If the teacher overrode the weight of the first item to 80%, the second item would automatically become 20% (correct) and the extra credit would also become 20% (incorrect).

The correct behaviour (after the fix): If the weight of extra credit item is not overridden, it should be itemmaxgrade / totalmaxgrade , where totalmaxgrade does not include the extra credit item. In the example, the weight of the extra credit item should always be 50%.

See MDL-49257 for further details including screenshots.