Recently, a question and its variants were posted on MSE (and cross-posted on MO as well, if that matters) using different new user accounts:

  1. https://math.stackexchange.com/questions/1422693/a-question-in-numerical-range
  2. A question in matrix polynomial (MO)
  3. https://math.stackexchange.com/questions/1422883/a-question-in-numerical-range
  4. https://math.stackexchange.com/questions/1423773/if-0-notin-wa-m-then-wp-lambda-is-bounded
  5. https://math.stackexchange.com/questions/1425116/a-question-in-numerical-range-of-matrix-polynomial
  6. https://math.stackexchange.com/questions/1427028/a-question-in-numerical-range

Question 2 is identical to question 1 and it was put on hold by some fellow users due to the question's lack of context. Question 3 asks whether the converse of the problem statement in question 1 is true or not. Technically it's not a duplicate, but one can avoid a new question if the "if" in question 1 is simply replaced by "if and only if". Question 4 is essentially question 1, but with a proof attempt (hence it is not "missing context or other details" and it cannot be closed as duplicate because question 1 receives no answer).

No one has yet answered any one of the above questions. I don't feel right about this guerilla tactic, but maybe I'm too pedantic. How to deal with such posting of many slight variants of a question? Is it OK to leave them be?

Edit: There is another stream of duplicates of the same theme, posted probably by the same user:

  1. https://math.stackexchange.com/questions/1383030/a-question-in-matrix-polynomial
  2. https://math.stackexchange.com/questions/1401518/a-question-about-matrix-norm
  3. https://math.stackexchange.com/questions/1405992/a-question-in-perturbation-of-p-lambda
  4. A question in compact set (MO)
  5. https://math.stackexchange.com/questions/1417453/a-question-on-matrix-norm
  6. A question on polynomial .
  • 2
    $\begingroup$ And each of the users is distinct. Making this yet another example. $\endgroup$
    – Asaf Karagila Mod
    Commented Sep 7, 2015 at 12:36
  • 22
    $\begingroup$ This is an unacceptable abuse of the site. The course of action I would take in this event is to flag for moderator attention (they can attempt to communicate with the user and possibly enact penalties that apply to more than just the user account), downvote (the excess questions are "not useful"), and vote-to-close (effectively duplicates). $\endgroup$
    – apnorton
    Commented Sep 7, 2015 at 12:42
  • 6
    $\begingroup$ All these are closed now. There were more (I remember coming across them about a week ago), probably deleted by now. $\endgroup$
    – user147263
    Commented Sep 7, 2015 at 15:01
  • $\begingroup$ Is it possible that these are homework questions, and that all of the posters are different students in the same class? That's a kind of abuse, but of a different kind than one person opening multiple accounts to ask the same question. $\endgroup$
    – Mars
    Commented Sep 13, 2015 at 17:28
  • $\begingroup$ @Mars It's possible but unlikely. You can easily see that the two streams of questions I mentioned in the OP shared the same theme, but the oldest one and the latest one were separated by more than a month. Several other questions with very similar settings also appeared on this site with the same user name ("H.S.", but using different accounts). E.g. math.stackexchange.com/questions/1430570/… and math.stackexchange.com/questions/1433266/… and one "H.S." $\endgroup$
    – user1551
    Commented Sep 13, 2015 at 23:17

2 Answers 2


This is an unacceptable abuse of the site, as it is more-or-less equivalent to reposting the exact same question multiple times due to impatience.

The course of action I would take in this event is to flag for moderator attention (they can attempt to communicate with the user and possibly enact penalties that apply to more than just the user account), downvote (the excess questions are "not useful"), and vote-to-close (effectively duplicates). We cannot close them as duplicates because of software restrictions, but the custom close reason (or perhaps "missing context") should be suitable here.

As to these particular questions, they have been successfully closed.

Comment-to-answer... sort-of.

  • $\begingroup$ What are these software restrictions? $\endgroup$ Commented Sep 17, 2015 at 0:45
  • 5
    $\begingroup$ @PyRulez: The SE software allows closing questions as duplicates only if a) the target has an upvoted or accepted answer; b) the questions were asked by the same account; or c) it's a child meta. None of those applied. $\endgroup$ Commented Sep 18, 2015 at 17:03

I see this is an unintended consequence of the unfriendliness of MSE towards new users. A person makes the effort to typeset a question, but the question lacks an articulated explanation of the problem, and it is immediately put on hold.

The first question listed by the OP has been put on hold because "This question does not appear to be about math within the scope defined in the help center". That's ridiculous: it is a concrete question about matrices, which is well within the scope of MSE.

This particular user seems to be fighting (unsuccessfully) for a workaround to people blocking his question. Looks like a natural reaction to me, and it highlights the problems created by the "closing brigade".

  • 12
    $\begingroup$ No, this user did not repost to get around the blocking of their questions --- they kept reposting to seek attention to their unanswered questions. Of all the questions in the first list, only the second one was closed after I made my report here, and it wasn't closed as a duplicate, but closed due to lack of context. Yet I do agree that the reason of closure given there is weird (but apnorton has stated his/her reason clearly in a comment), and personally, I don't agree to close the first question in the list because it is the headwater question. $\endgroup$
    – user1551
    Commented Sep 11, 2015 at 17:45
  • 6
    $\begingroup$ As to the unfriendliness of MSE towards new users, I agree that this is true to some extent at large. But in this particular case, before I wrote my posting here and before any close votes were cast, another user (Paul Sinclair) and I had been trying to help. Our comments to the first question on the list are still there. Yet this user did not respond but reposted. $\endgroup$
    – user1551
    Commented Sep 11, 2015 at 17:57
  • 11
    $\begingroup$ Someone makes the effort of copying a question from a textbook, and math.SE users don't fall head over heels to answer it. What a shame. Anyway here is one of the numerous threads about the "off-topic" classification of such questions. I thought you were "scared away" off the website? $\endgroup$ Commented Sep 11, 2015 at 18:05
  • 5
    $\begingroup$ @NajibIdrissi: I wasn't scared away from the website when I first came because I used the site to answer questions and not to ask them, and usually not in the mainstream topics. People with your attitude would have certainly scared me away if I had come as a newbie, and they are the cause of me using the site a lot less these days. . $\endgroup$ Commented Sep 11, 2015 at 18:20
  • 2
    $\begingroup$ Uhh, the "after" in my first comment should read "before". In short, all of the user's questions (except the second one on the first list) were reposted before any close votes were cast. $\endgroup$
    – user1551
    Commented Sep 12, 2015 at 7:17
  • 6
    $\begingroup$ Martin to prove any possible unfriendliness towards new users, you need to bring up something concrete; some evidence of new user being treated as harsh. We both know why there are close votes, and they're not always justified. And sure, the user may be unintentionally doing what he does. But you need to be objective if you want people to accept what you say. For instance, why should this be reopened? Your answer's supposed to address that to get your message across, but instead you're just saying "you closed that and the reason sucks." $\endgroup$
    – M.A.R.
    Commented Sep 14, 2015 at 21:09
  • 9
    $\begingroup$ Much of this "unfriendliness toward new users" wouldn't exists if the new user would simply read and follow the instructions on how to properly ask ask a question on this site. $\endgroup$ Commented Sep 19, 2015 at 15:35

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .