# Tags that encourage off-topic questions

MathOverflow has a few problematic tags which are not inappropriate by themselves but suggest off-topic ideas. A prime example of this is the calculus tag. Sometimes a research-level mathematics question does involve some calculus so it is not inappropriate to tag such questions in this way. However — and very clearly so — not all calculus questions are research level!

Should MathOverflow:

1. Eliminate the calculus tag.
2. Keep the calculus tag but carefully pay attention to its usage.
3. Keep the calculus tag.

The ideal solution is option 2 but this is simply not feasible. In this case, option 1 is perhaps the best solution but what about less obvious cases like linear-algebra?

(If you think of a similarly litigious tag, please post an answer similar to the calculus model below so it can be debated separately.)

• My gut feeling (perhaps not borne out by cold look at evidence) is that "linear algebra" remains a useful general tag that can be applied even to questions at research level – Yemon Choi Aug 18 '13 at 23:07
• Eliminate "calculus", there are obvious alternatives. "Linear algebra", on the other hand, seems useful, even if it attracts some noise. – Andrés E. Caicedo Aug 18 '13 at 23:09
• I agree with Andres. – Bill Johnson Aug 18 '13 at 23:10
• For linear algebra, to give an example, we recently had the very interesting question mathoverflow.net/questions/139595/…, which seems to me to be an entirely appropriate use of the tag. – Joel David Hamkins Aug 18 '13 at 23:11
• Also, the tag 'linear-algebra' is commonly used as a sort of replacement for a top level tag. I believe there are many valid questions which, other than 'linear-algebra', have only very specific tags. Personally, I feel that questions involving linear algebra are often hard to shoehorn into the usual top level tags. [Perhaps that means we should adopt new top level tags, but that is an entirely different discussion.] – Ricardo Andrade Aug 18 '13 at 23:48
• On a different note, if you are looking for tags which invite problematic questions, look no further than the deprecated tag 'geometry', which is much larger than 'calculus'. – Ricardo Andrade Aug 18 '13 at 23:50
• Strangely, trigonometry seems to be majority questions that are at least decent. Otherwise I'd suggest getting rid of it too. – Logan M Aug 19 '13 at 0:06
• @Ricardo: That was indeed an entirely different question - meta.mathoverflow.net/questions/196/use-of-arxiv-tags – François G. Dorais Aug 19 '13 at 0:07
• @LoganMaingi: That should be an answer so it gets proper notification to the community. – François G. Dorais Aug 19 '13 at 0:08
• At the risk of thread drift, I refer readers to a question recently posed at m.se, as to whether there are any open problems in linear algebra: math.stackexchange.com/questions/461017/… – Gerry Myerson Aug 19 '13 at 0:13
• In connection with this problem, it might be useful to know how many posts bear only the tag which is going to be burninated. (Which, I guess, means that these questions would have (untagged) as their only tag.) You can use this query for various tags. – Martin Sleziak Aug 19 '13 at 9:41
• One contrary data point: I used "calculus" as the first tag of my MO question "Source and context of $\frac{22}{7} - \pi = \int_0^1 (x-x^2)^4 \frac{dx}{1+x^2}$" (mathoverflow.net/questions/67384). The question got interesting and pertinent replies, and nobody suggested that either the question or the tag were not appropriate for MathOverflow. – Noam D. Elkies Aug 20 '13 at 4:49
• Maybe it's time for this question to get a new title. – Mark Meckes Aug 26 '13 at 13:42
• @Amir: No, that would suggest that this is the only criterion when it's only one of them. There are a variety of differences between calculus and linear algebra, different users will see different ones and vote accordingly. The total vote count should then approximately reflect all aspects and perspectives. If you feel that one aspect is being ignored in one case or another, add a comment highlighting your point of view so that others can see what they are missing out on. For example, Andres pointed out the alternatives aspect in a comment above and 19 users agreed that this was important. – François G. Dorais Aug 29 '13 at 14:58
• I think nt.number theory attracts more than its fair share of off-topic questions! – Lucia Jan 23 '14 at 19:57

Vote up/down if you think the tag should/shouldn't be deleted.

I consider this as disruptive/having the potential to create off-topic questions as asking for advice on something has a conotation of some 'personal' question. This hardly ever makes a good MO question. Besides, it is basically meaningless as a tag, since most any question can be also construed as aking for advice on some thing or other, how to prove something, how to go about learning something, how to apply for a job, how to teach a course,... each of these might or might not be approriate MO question but they have little in common. The main use case in practice seems to be to tag 'career' and 'advice' so the latter feels somewhat redundant then too.

Vote up/down if you think the gm.general-mathematics tag should/shouldn't be deleted.

• Presently, gm.general-mathematics has no tag wiki, and at least to me it is not clear how to understand "general mathematics" -- maybe in the arXiv sense? – Stefan Kohl Aug 26 '13 at 20:00
• Dear @Stefan: I too have little idea what the tag 'gm.general-mathematics' stands for. It feels a bit like a dumping ground for random questions. On the other hand, perhaps that just means we should collectively agree on a meaning... – Ricardo Andrade Aug 26 '13 at 23:01
• arxiv.org/archive/math : Mathematical material of general interest, topics not covered elsewhere – François G. Dorais Aug 26 '13 at 23:04
• Would it be more aptly renamed gm.general-interest? (Topics not covered elsewhere doesn't make sense here.) – François G. Dorais Aug 26 '13 at 23:07
• @FrançoisG.Dorais I think we should think twice before changing names away from arXiv names.// Also I think this one shoudl definitely be kept, except we change the top-level structure completely. – user9072 Aug 27 '13 at 9:57
• @quid: Our arxiv tags already don't match the names exactly because of character limits. There weren't many issues when we changed ca.classical-analysis to ca.analysis-and-odes. – François G. Dorais Aug 27 '13 at 10:10
• @FrançoisG.Dorais perhaps I am sometimes a bit too worried. Still, I am not sure general interest is that much more intuitive. Also I disagree that topics not covered elsewhere doesn't make sense here. It makes almost as much sense as on the arXiv; in principle, this top-level tag were to be used when none of the other top-levle tags fits, just as on the arXiv. Sure, very few do this (I do sometimes). – user9072 Aug 27 '13 at 12:36
• @quid: By the way, I remember having heard that some people translate the "GM" in math.GM on arXiv as [G]arbage [M]achine, reflecting that at times arXiv moves low-quality papers from the more specific sections there. I wonder whether it is generally perceived in this way, and whether people might read the "GM" here on MO in a similar way. – Stefan Kohl Aug 27 '13 at 13:31
• I never remove another fitting top-level tag to tag it gm, but if I do not find a fitting top-level tag chances are the question is not really a research-level question. – user9072 Aug 27 '13 at 14:11

Vote up/down if you think the tag should/shouldn't be deleted.

• (This request was formerly for the recreational which was since renamed to recreational-mathematics.) – François G. Dorais Aug 26 '13 at 2:39
• I am a bit curious about the downvotes. The very definition of this tag pretty much makes any question tagged with it off-topic (after all, hard does not imply being of interest to research mathematicians). I would like to see the questions tagged with this which are interesting be redirected to MSE, where they are more clearly on topic. – Tobias Kildetoft Aug 26 '13 at 9:11
• @Tobias: Maybe you don't understand what the tag means: recreational mathematics is the application of mathematics to the design of games and puzzles. – François G. Dorais Aug 26 '13 at 12:03
• @FrançoisG.Dorais In that case the tag is in desperate need of a wiki and tag excerpt, as that is not the meaning most people would associate with the term. – Tobias Kildetoft Aug 26 '13 at 19:12
• @Tobias Kildetoft. I disagree with both the main and the parenthesized parts of your second sentence. For me recreational math. is just everything that just doesn't fit into any "big theory" or "grand scheme". 80% of Joseph O'Rourke's questions are like that (though he seldom uses this tag himself) and I'm not the only one enjoying his "jeux de l'esprit" here. – fedja Aug 26 '13 at 21:34
• This reminds me of someone I met a few weeks ago who told me that he preferred his math to be boring and easy rather than exciting and challenging. À chacun chacun son goût... – François G. Dorais Aug 26 '13 at 23:12
• After the addition of the tag excerpt, I too agree that this tag should not be deleted (I can't change my vote without editing the answer, and I didn't feel like bumping this thread for it). @fedja Are you claiming that being hard does imply being of interest to research mathematicians? It is easy to come up with hard problems by taking some random collection of integer polynomials, adding one or more parameters and asking when integral solutions exist, but unless one does this carefully, I doubt people will find it interesting. – Tobias Kildetoft Aug 30 '13 at 8:22
• My meaning of "hard problem" is "being hard+being a problem" (the latter means that either someone else should be really interested in it, or it should have enough intrinsic beauty to attract me). I just oppose the default meaning of "interesting", which nowadays seems to be "fitting my field and motivated by something related to my research". As to "random polynomials", if you pose it as "Given a reasonable distribution on the set of polynomials, what is the probability that the random system of $n$ Diophantine equations has a solution?", I do not see why it is "not interesting". – fedja Aug 30 '13 at 11:18

Vote up/down if you think the conic-sections tag should/shouldn't be deleted.

Vote up/down if you think the inequalities tag should/shouldn't be deleted.

• It is a legitimate branch of analysis. The questions in this category can range from trivialities to technical nightmares to hopelessly looking open problems, of course, but isn't the same true about any other branch of any other field? – fedja Aug 26 '13 at 21:24
• I agree with fedja, this tag should be kept. I guess there is a tag (estimation-theory) that could be used if this is deleted. – Gerald Edgar Mar 27 '14 at 16:16

Vote up/down if you think the linear-algebra tag should/shouldn't be deleted.