Allocation of choices

[NinaHerrmann]

Unfortunately, I don't have exact reproduction steps.
After our upgrade to v4.2-r1 we had an error allocating choices suboptimal when allocating remaining students. We ran the algorithm several times, not able to get a different result. Deleting the choices in the DB solved the issue. This might also be related to running tasks in the background, or changing the number of students per choice (unfortunately the teacher was not very specific about it).

This issue is created to track if anyone experiences the same problems.

[PhMemmel]

What exactly does "suboptimal" mean?

[NinaHerrmann]

We can not upload the complete data, in short, people who did not participate were allocated to choices that were chosen by people who participated. In the Screenshot row three was allocated to an unrated choice, while the choice was allocated to someone who did not participate at all (last row).

[PhMemmel]

Are we talking about the basic algorithm that distributes users with a vote or the new feature which distributes users who have not voted?

If it is the latter:
This feature distributes users who did not vote and thus the algorithm does not look at the users' votes at all. If these users voted the basic algorithm would be expected to distribute them according to their votes. Only after that a distribution of the other users who did not vote makes sense.

[NinaHerrmann]

The problem is I can not exactly tell you what happened as the person in our System who had the issue was not really precise. (Sorry to disappoint you)
We think the steps were:

1. Some users made choices
2. The Algorithm was running
3. Other users were allocated to the choices by the new feature
4. Choices were changed to allow only 15 not 25 people per choice
5. The algorithm was run again.

[PhMemmel]

I see. Then I would suspect that both algorithms worked fine. The way to solve this as user would be:

• ...
• Change limits of choices
• Rerun initial algorithm (this one clears out all allocations and runs from the beginning)
• Then apply the second algorithm to distribute the unallocated

Important information: Algorithm for distributing unallocated users does not clear current allocations, but only tries to distribute still unallocated users.

[NinaHerrmann]

Rerunning the initial algorithm did not solve the problem. @Laur0r also suggested that but it did not change the allocation.

[PhMemmel]

Oh I see, so there might be a bug indeed. Thanks for clarifying 🙂

[NinaHerrmann]

No problem, however as I said, I am not sure if the teacher might just messed things up, so I will wait until someone reports the same problem 😂