Understand question revision incompatibility

In order to perform assignment regrading, you'll first have to make a compatible revision to a question contained within the assignment.

The revisions made to a question must satisfy the compatibility requirements of Möbius in order for a regrading job to be completed successfully.

A question revision incompatibility indicates that a revision was made to a question so that it can't be regraded properly against the Current Revision.

The Regrade page displays information about these compatibility details.

The Möbius compatibility utilities detect two main types of incompatibilities related to question revisions during assignment regrading.

However, there are still some limitations when it comes to detecting all question revision compatibilities.

Types of incompatibilities

If incompatibilities are detected, two issue types can occur when regrading an assignment with a question revision:

Undetermined incompatibility
Total incompatibility

These incompatibilities are shown with icons in the Revision panes on the Regrade page:

Undetermined incompatibility

The undetermined incompatibility icon indicates that it can't be determined whether the question revision is compatible with the Current Revision for regrading.

The regrade is permitted with the question revision.

Hovering your cursor over the undetermined incompatibility icon notifies you of the type of incompatibility:

Clicking on the undetermined incompatibility icon gives a more specific explanation of the issue causing the revision incompatibility:

Total incompatibility

The total incompatibility icon indicates that the question revision isn't compatible with the Current Revision for regrading.

You're then blocked from assignment regrading using this question revision.

Hovering your cursor over the total incompatibility icon notifies you of the type of incompatibility:

Clicking on the total incompatibility icon gives a more specific explanation of the issue causing the revision incompatibility:

Compatibility utilities limitations

It's possible to make question revisions in such a way that existing responses won't be regraded as you intend.

Notable limitations of the compatibility utilities during regrading are:

General — Changing question text or images won't be recognized.
Indexed Response (Example — matching, multiple choice, sorting, clickable image) — These question types store the correct response based on the index (position) of the response option (index 1 is the first response option, index 2 is the second response option, etc.).
- Any question revisions made to the actual content of the response options don't affect the correctness of the response.
- Only changes to the index are recognized to modify response correctness.
Algorithms — Changing existing algorithmic variables won't be recognized.
- The original state of the algorithm is used.