Prompted by Gro-Tsen's recent meta question, it appears that now may be a good time to rethink our site-specific close reasons here on MathOverflow.
If you have sufficient rep, you can click the "close" button on a question (or the equivalent "flag" → "needs improvement", which is available for almost all users), and you get a popup which looks like this:
These are some general close reasons common to the entire Stack Exchange network as I understand, and which, if we wanted to change them, would at the very least require some discussion with Stack Exchange (and they might tell us no).
What we do have control over is the options you get if you choose the second option on this list -- the community-specific reasons. If you do that, you get the following options:
We currently have two options here, and we can have up to three. As a technical point, it appears to be possible for moderators to delete a close reason or to create a new one, but not to edit the description in an existing close reason. We can also tinker with the order they appear in.
It's hard to trace these sorts of things all the way back to the beginning of MO, but in addition to the current two site-specific close reasons, the software currently remembers two deactivated ones, which read:
MathOverflow is for mathematicians to ask questions to each other about their research. Questions about homework are generally off-topic.
Questions about homework are generally off-topic. MathOverflow is for mathematicians to ask each other questions about their research.
I suspect that one of these reasons at some point replaced the other, as a minor rewording. Judging by this old meta discussion, it appears that this close reason (containing the word "homework") was retired in 2013 in favor of the current close reason which mentions Math Stack Exchange. At the time, no specific rationale was recorded for dropping the word "homework", but I think I agree that explicitly labeling a question as "looking like homework" is not something we want to be doing in our question-closing process.
Why do we close questions, anyway?
We have recently revamped the help page which describes what's on-topic and what's off-topic on MathOverflow, as suggested by Matt F. in this meta discussion. Currently, that help page lists the following possible reasons that a question may be off-topic:
The question looks like homework.
The question is a discussion question.
The question asks for a broad exposition or encyclopedia article on a topic.
The question asks for OP's or somebody else's work to be checked.
The question is really just an announcement of results.
The question asks a well-known open problem.
The question has been inappropriately cross-posted on another site.
The question is a meta MathOverflow question.
In addition, the user is advised to avoid the following types of questions until they gain a bit of familiarity with the site:
Questions asking for a list of something.
Questions about the workings of the mathematical community rather than about mathematics per se.
Question 1: Are we missing any important close reasons here?
Analysis of Close Reasons Needed:
It appears to me that, with a few exceptions, most of the above close reasons are well-covered by the close reasons one is allowed to select when voting to close a question:
Homework -- not about research math.
Discussion -- needs focus / opinion based.
Encyclopedia -- needs focus.
Checking work -- ?? As suggested by Gro-Tsen, we could perhaps use a specific close reason for this.
Result announcement -- ?? If the question is not really a question, in principle we shouldn't need a site-specific close reason. Probably "opinion-based" should cover cases like this. But perhaps there's something to be said for having a close reason which allows this to be lumped with "work-checking".
Open problem -- ?? I think that "needs focus" should cover a case like this -- the point is that if you're asking about an open problem, you should be asking some more specific question than just "what is the solution?". However, because "needs focus" is not a site-specific close reason, we can't edit it to point out that specifically, questions about open problems need a very particular kind of focus. So perhaps it would make sense to have an additional close reason covering this case.
duplicate?? I realize now I'm not sure how we usually handle inappropriate cross-posts.
Meta -- not about research math.
(Lists) -- needs focus.
(Mathematical community) -- not about research math.
So by my count, there are up to
3 4 close reasons which could be formalized in addition to the ones we have, but only 1 slot to put them in. So some sort of prioritizing or lumping-together needs to be done.
Question 2: Which of the
3 4 close reasons with question marks above is the most important to give a close reason to? More broadly, what would be the ideal way to use our 3 allotted slots of site-specific close reasons?
For example, one possibility would be to keep the two existing close reasons we have, and to additionally add something along the lines suggested by Gro-Tsen. In that case, we'd just need to nail down the details a bit more.
(Note that there's also the option to provide a custom close reason which you write on the spot. If a close reason is rare enough, it can be covered by that.)
Analysis of the close reasons we have:
Note also that the two site-specific close reasons we currently have are similar -- one is "not about research math", while the other is "not about research math, and here's a link to Math.SE". It seems to me these should be modified to give a little more clarity about when one should be chosen over the other. This leads into the final point.
Since 2019 we have the flexibility to have the close reasons we use display differently to different users. For instance, the message shown to a prospective close voter can be different from the message shown to a prospective close votee.
I bring this up because it may be relevant to us when it comes to the two existing close reasons -- we could consider adding some guidance for close-voters over when to choose the one which links to Math Stack Exchange and when not to (I think the main point is: don't choose the Math Stack Exchange one unless you're sure the question meets the standards of Math Stack Exchange questions.)
What specifically should our site-specific close reasons say?
This question is mean to include the specifics of any potential new close reasons, as well as any potential changes to the wording of existing close reasons (technically to change the wording, the process is to delete the old close reason and replace it with a new one, but I think we should be open to doing something like that at this time with our existing close reasons.)