Explanation of Algorithm? Which notion of fairness?

[Pibborn]

Dear maintainers,

thank you for your contribution! My institution is offering this plugin, and while I am overall knowledgeable about minimum-cut algorithms, I am not 100% sure what is "fair" about the allocation returned by the allocation algorithm implemented here. I will provide some examples to make my point (hopefully) clear:

• Is the returned allocation the one that achieves the minimum average cost? Or, equivalently, is it the one that maximizes user preferences on average? This was originally called, I think, the "hungarian method"
• Is the returned allocation the one that minimizes the maximum per-student cost? As an example, is this an allocation that works so that no student gets their least favorite option? The example is not completely general, but hopefully gets there. I don't want to write formulas, but I can if that is helpful :)

And there are of course other notions of fairness, but these are the ones that are coming to my mind immediately. I will also note that this information was not immediately available to me via the repo README or the moodle.org website, something that could perhaps be fixed in the future.

Thank you in advance!