Not signed in (Sign In)

Vanilla 1.1.9 is a product of Lussumo. More Information: Documentation, Community Support.

    I am not optimally positioned to pose nor comment on this issue, because I neither participate fully in MO nor especially in MSE. Many others exceed my participation in both forums, and I respectfully defer to their more informed opinions. But from my limited perspective, I sense that these propositions may hold true:

    1. MSE absorbs recently more of the homework (or HW-like) questions, reducing those on MO (sometimes via referrals).

    2. MO retains an undiminished level of "soft questions"---MSE has not mitigated this "problem" (in so far as it is a problem---opinions vary).

    3. MSE attracts a number of high-quality research-level questions that formerly would be directed to MO; and MSE responses are sometimes indistinguishable in expertise from MO responses.

    I am least certain of #3 above, and that is my main concern. There are several highly knowledgeable users who participate in one of {MO, MSE} but not the other. I am wondering if the research mission of MO is somewhat fractured in this respect by the existence of MSE? I have no suggested solutions to offer, just a vague worry to convey at a potential fracturing of the scarce resource of knowledgeable and willing contributors.
    • CommentAuthorHarry Gindi
    • CommentTimeNov 6th 2010 edited

    Dear Joseph,

    I'm not aware of MSE attracting a high number of research-level questions that don't originate from Akhil Mathew, Qiaochu Yuan, or a few other high-level undergraduates here who, as a sign of (false?) modesty, have decided to ask their questions there rather than here.

    At least as far as those two are concerned, I think that if MO requests that they ask questions here rather than there, they would happily return to asking questions here.

    Thanks, Harry. I defer to the opinion of those who have paid more attention to the daily traffic on MSE than I have.
    I think it's inevitable and fine that there be some overlap between the hardest questions on MSE and the easiest questions on MO. If we ever become a SE 2.0 site then it would be possible to migrate questions between sites and it might be more reasonable to want a bright line, but as it is I think it's fine that the two sites have overlapping distributions as long as the average question on each site is different enough that the sites feel different.
    It's not a question of modesty; for most of the questions I ask on MSE, I would be genuinely uncomfortable asking them on MO. I think the level of MO is a lot higher than it used to be, say, a year ago -- there are much fewer soft questions, and most of the questions that do exist require considerable expertise. There are plenty of graduate students that ask their questions on MSE instead of MO. If I ask an elementary question, I would rather ask it on MSE first, because if it turns out to have a simple answer, it will be a much less embarrassing situation.

    (I actually find it interesting that the level on MSE has also bumped up considerably since its founding days. I remember that in the first week, I could answer almost all the questions without much thought, but now I am able to answer very few.)
    • CommentAuthorEmerton
    • CommentTimeNov 6th 2010

    In fact almost all the high-ranked (say top 20) contributors on Math.SE seem to also participate in MO, so there doesn't seem to be much danger so far of expertise being lost to one site or another.


    MSE has now posted 23,993 questions, surpassing MO's 23,992 questions. I don't know the exact birthdates of each forum, but MO is roughly twice as old as MSE. Like the porridge, I find MO's question-rate, which I guess to be 40 questions per day, just about right. MSE's at about 100 questions per day is too hot for my tastes, and CSTheory's 10(?) per day too cool. :-)

    • CommentAuthorquid
    • CommentTimeOct 13th 2011 edited

    Not being active on MSE (and only looking there on occassion) I am neither well placed to judge this in detail.

    However, it is from an MO persepective my opinion that a certain type of question that in my opinion used to be more present on MO, and I assume this is precisely the type that now might be asked on MSE, starts to be lacking on MO. What I mean are perhaps too vaguely described "solid graduate level questions" (not the most standard textbook-excercise question from some graduate Analysis or Algebra course but, quoting the FAQs emphasize mine, "the sorts of questions you come across when you're writing or reading articles or graduate level books"; in other words question that are a bit beyond what one can find in any book on the subject but questions that might come up when thinking beyond what one read).

    I believe that, ultimately, it is the smaller number of this type of questions that causes the at first glance paradoxical situation that on the one hand some people say that the level of MO significantly increased while at the same time I see some (at the strict/high-level end) users say that MO used to be better.


    I think quid's comment is exactly right.

    • CommentAuthortheojf
    • CommentTimeOct 13th 2011

    Echoing quid: when we started MO, I know I asked a number of (naive) graduate-level questions. I am, of course, still "graduate level", but the questions I've been thinking about more recently are more focused, and either things I would like to think about privately, or things that I know the one expert to email and ask. I do hope that MO has (or continues to have) "graduate level" questions; for example, questions of the form "this came up in my class on ..., and the professor didn't know the answer off the top of her head" are, I think, very appropriate.

    The question asked by Joseph O'Rourke Nov 6th 2010
    so it is more than 1.5 y ago. But it seems to me it is still in air :) Especially item 3:

    3) MSE attracts a number of high-quality research-level questions that formerly would be directed to MO; and MSE responses are sometimes indistinguishable in expertise from MO responses.

    I am not convinced by Harry's or quid's answer.

    I have some ideas by let me keep them with me for the moment.
    Let me just mention my own examples (very few 3-4 post)
    of posts on MSE, not MO (which might be suitable for MO):
    when I do not have enough time to analyse whether a question good enough
    (or I afraid that this analysis might take more time than I have)
    but I am fired by curiousity:) I posted them on MSE.

    Let me mention that the answer
    by Jyrki Lahtonen is very cool.
    As well as some other answers by David Speyer
    • CommentAuthorJDH
    • CommentTimeJul 15th 2012 edited

    In my experience on both forums, it is certainly true that MSE attracts a large number of questions that rise to the MO level and would be appropriately placed on MO. For example, there are 35 questions tagged with the topic of forcing, many of which could be placed or are better placed on MO in my opinion (I hold that almost any nontrivial question about forcing is fine on MO). And I have similarly seen numerous advanced questions on large cardinals and other topics that I find more appropriate for MO than MSE.

    The problems with this are two-fold:

    • First, while such more sophisticated questions do get knowledgeable answers on MSE, and there are definitely talented people there, it seems to me that they would get more and better attention on MO than they do on MSE, where such question often have fewer views and votes than they would earn on MO.

    • Second, the existence of such a kind of level of questions on MO is important for the success of MO in the long run, and losing them to MSE hurts the operation of MO. In order to succeed, MO must have a large base of particpating interested users, who are checking out the questions and making posts. If the site should become populated only by super-advanced, highly technical questions, as some seem to have advocated, then I would simply expect the site to whither, with fewer and fewer participants, since even knowledgeable users will find less and less of interest, and so they won't be here to answer those advanced questions for which they do know the answer.

    Thus, I believe it is important for the robust livelihood of MO to retain a greater number of those questions on MO, and to redirect them from MSE to MO. We should strongly encourage the posting of solid graduate-level questions on MO. I would suggest that the undergraduate/graduate divide is the right place to draw the line between MSE and MO.

    The importance of this issue for the success of MO makes me look upon it as an argument for the transition of MO to become a stackexchange 2.0 site, or whatever it is called, provided that we had a capability to move questions from MSE to MO. For example, perhaps users could vote to kick a question from MSE to MO and vice versa, much like voting to close. This way, advanced questions on MSE would find their way to MO, and we could more easily and more finely cultivate a difference in level between the sites.


    Why did you post those questions on SE, Alex? It is pretty obvious that they are MO level questions.

    • CommentAuthorWill Jagy
    • CommentTimeJul 15th 2012 edited
    On Joel's observations, I enjoyed this article (May 14 New Yorker) about a business professor who has improved understanding of when a company focusses too much on their most expensive products and lets someone else provide the cheaper stuff, leading eventually to ruin. Even the Joint Chiefs of Staff asked this guy how to proceed in the era of terrorism. I think a case can be made for research level questions being the most expensive products (high quality steel) for the best customers and calculus questions being rebar.

    Anyway, his insight was not so much that those who want to buy cheap outnumber those who want to buy the best, the lesson is more that the companies supplying the best could also have sold cheaper products without difficulty, but chose not to do so. I'm not sure where that puts MO, MSE is already under separate control.
    May be I am mistaking, but briefly browsing the list of users on MSE I see some researchers who are present and active on MSE, but not on MO.
    If it is true then this seems to me the main problem for MO - if some research level people feel themselves better on MSE.
    If it is so, then, of course, one would have many high level questions on MSE, and it would not be possible to move them to MO, since people will not want this. Is it true ? If yes what might be the reason ?

    There are at least 2 MO users with non small reputation who migrated from MO to MSE, I am curious what is the reason ? But probably these are exceptions.

    As for me MSE has obvious disadvantage that there are so many low level questions, than I just do not know how to navigate there.

    @JDH how do find some interesting question there ? By "tag" ?

    @Bill Johnson it was not "pretty obvious" for me, any way asking such question on MO I would feel obliged to provide more background, analysis etc... but at the moment of asking I did not have time/ability to do it.

    @Will, the problem is that the way I see it many of the participant who come here for the gold, are less than happy to stay when there is too much led.

    I do agree with Joel's point. I am certainly guilty of taking these sort of questions to MSE, more than once too. I will try to favor MO in the future.

    JDH wrote,

    "The importance of this issue for the success of MO makes me look upon it as an argument for the transition of MO to become a stackexchange 2.0 site, or whatever it is called, provided that we had a capability to move questions from MSE to MO. For example, perhaps users could vote to kick a question from MSE to MO and vice versa, much like voting to close."

    This is already implemented at MSE. When I vote to close a question as off-topic, I'm given the option of ticking a more suitable stackexchange site for the question. I imagine that if MO goes to SE, one of the options offered for migration from MSE will be to MO (and presumably the other way, as well).

    As things currently stand, I never vote to close a math question of any sort as off-topic at MSE. I may occasionally leave a comment that if the poster gets no satisfactory response after a couple of days then the poster might consider using MO.
    Will young users who are now undergrad and get accustomed to MSE migrate to MO, when they become grads ?
    May be it is better to zero the reputation every year to decrease of unhappiness of new users ? :):)
    @Alex Chervov: The way I navigate math.SE is to go to and scroll down a few screens. Questions that remain unanswered for more than a few hours are a much more interesting population than math.SE questions in general.
    • CommentAuthorWill Jagy
    • CommentTimeJul 16th 2012
    Asaf and Alexander, yes, the advantage of MSE being in place is some reduction in the proportion, on MO, of poor or poorly worded questions.

    Among the most valuable aspects of MO for me personally has been the instances when knowledgeable mathematicians take the time to post illuminating answers to naive questions, for example:

    "If the site should become populated only by super-advanced, highly technical questions" (JDH), we would lose this enjoyable educational aspect.

    • CommentAuthorGeorg
    • CommentTimeJul 25th 2012
    I am only a silent reader of MO. My opinion is that MO and MSE should merge under the following technical model:

    There are four categories:
    - research
    - graduate
    - undergraduate
    - low level

    Each question is categorized belonging to one of these categories.
    To categorize only professional users (>5k reputation) are entitled. Default is low level.

    On the top of each page there are four buttons:
    research | graduate | undergraduate | all
    Pressing such a button filters the questions belonging to the category.

    Some advantages:
    One place to go, for readers as for contributors.
    The categorization is by democratic rule.
    No more meta-discussions of the sort 'Would it be acceptable to ask the following question?'.

    I think this model brings together the advantages of both sites.
    • CommentAuthorjonbannon
    • CommentTimeJul 25th 2012 edited
    I think this thread is very important. If MO had as many homework posts as MSE I'd stop visiting the site. On the other hand, it is nice to have someplace to ask soft or routine things. The idea of a merger seems pretty interesting. Filtering questions by level could be a great way to stop MO from suffering breakneck speed of posts as MSE does. On the other hand, if one wants to think about something easier or harder one could change the filter.

    Personally, I ask questions at MSE when I'm pretty sure they are trivial or too soft for MO. It would be very cool if this didn't require going to more than one site.

    Are there any obvious drawbacks to the idea of a merger? One possible drawback is the following: MO reputation is earned by answering research-level questions. MSE reputation can be earned by answering tons of ridiculous homework questions. I'm hesitant to think that the integrity of MO would be maintained if one could earn rep by holding infinite office hours. On the other hand, it has been noted that the high rep users of MSE have large overlap with those of MO, so this liquidity of reputation may not be a problem at all. (In fact, the super-user overlap here is evidence that such a merger may be able to work, and would probably be great for both sites...since the communities would merge.)

    I'm still scared that a merger would undermine MO's commitment to avoiding answering homework problems (they'd be coming in the back door). Would the level filter buttons stop this?

    MSE is too big as it is. I think that the idea, while interesting and has its merits, is futile and will only cause MO to decline.

    • CommentAuthorGeorg
    • CommentTimeJul 26th 2012 edited
    jonbannon: "MO reputation is earned by answering research-level questions.
    MSE reputation can be earned by answering tons of ridiculous homework questions."

    This is easy to overcome on the engineering level by introducing weighted sums.
    A '+' for a low-level question earns 0 reputation points , for undergraduate
    questions 1 rep, for graduate questions 2 rep and for research questions 4 rep,
    for instance. Upon reflection this kind of differentiation would even bring benefit
    to MO by displaying a much more precise reputation profile of the users than there
    is now -- of course this is impossible here because of the false assumption that
    all questions here are research questions.

    Asaf Karagila: "MSE is too big as it is."

    In what sense? For me (and others) MO is also too big in the sense that there are
    much too much non-research questions here. From the idea of using filters also
    people only interested in research level questions will benefit.

    I find your statement "I am only a silent reader of MO." contradicting in some sense the one from your last post "For me (and others) MO is also too big..."

    MSE is too big in the sense that if you actively participate in the site you easily see that in a very definitive way, MSE has too many questions and it became very hard to browse it already. Oh, before you suggest I use filters and all sort of hacks, I am using those. MSE is too big.

    What you suggest is simply put MO and MSE on the same site and same users repository. I think it is not a good fit. Much like active research is not usually done in high school corridors, and for a good reason my office is located in the mathematics department building, rather than the high school outside the university.

    Furthermore, if you think that MO is too big then perhaps it is time to add such features as you suggest to MO directly, without forcing users to filter through dozens of homework questions per day.

    It's been about six years since all browsers include tabbed browsing support. If someone has a problem opening another tab, this is unfortunate, but it probably hints that they will have a hard time coping with complex filtering as well. These users, if they are using MO right now, are likely to cease; and if they could learn how to work with such convoluted interface, they can probably learn how to use tabs in a browser to open two different sites at the same time.

    • CommentAuthorGeorg
    • CommentTimeJul 26th 2012
    JDH wrote:

    "The importance of this issue for the success of MO makes me look upon it as an
    argument for the transition of MO to become a stackexchange 2.0 site, or whatever
    it is called, provided that we had a capability to move questions from MSE to MO.
    For example, perhaps users could vote to kick a question from MSE to MO and vice
    versa, much like voting to close."

    This kicking "a question from MSE to MO and vice versa" would be replaced in
    my technical model by trying to change the category by assigning a category
    which is more appropriate. Much simpler and natural I think, less dependent
    on the implementation, less touching the feelings of questioner. And with the
    added advantage to differentiate finer.

    Just wondering, how would that be different than the current SE 2.0 network? You have many sites and you can filter the questions accordingly, or just meld them all into a big pot. You get notifications for all the sites you participate in at the same convenient location; and it still sports the needed partition that people from MSE cannot interfere too much with TEX.SE, and vice versa.

    So how would your suggest be any real improvement to simply "Migrate MO to SE2.0"? (something that I currently in favour of not doing, by the way)

    • CommentAuthorGeorg
    • CommentTimeJul 26th 2012 edited
    Asaf Karagila :
    "..they will have a hard time coping with complex filtering as well"

    The filtering I suggested is not complex and is done by the software, the
    use of the four buttons
    [research] [graduate] [undergraduate] [all]
    will not, I am certain, overstrain MO users. Their might even be a default
    for logged-in users, which can be set by the user in his preferences.

    Asaf Karagila :
    "Much like active research is not usually done in high school corridors, and for
    a good reason my office is located in the mathematics department building, rather
    than the high school outside the university."

    The binary building I am speaking about is different: The chance that
    you meet on its corridors people you do not want to meet is, by construction,
    /less/ than in the current MO building.

    So it would become more attractive for anyone, including researchers,
    the incentive to participate will rise, the time lost by looking through
    the heap of posts for the relevant pieces of information will decrease.
    George, there is no way that Stackexchange will implement the possibility of awarding reputation according to tags.
    • CommentAuthorWillieWong
    • CommentTimeJul 26th 2012

    (continued from Michael's comment) ... especially since tags are mutable.

    On the other hand, in both SE and SE2 by visiting a user's profile you can see a list of tags in which they have earned upvotes. So if you want to see a user's "specialty areas" it is not too hard to find that information.

    (Incidentally, "specialty area" should be read as nothing more than the areas in which the user chooses to ask and answer questions; my profile is only loosely correlated with what I do in real life.)

    • CommentAuthorGeorg
    • CommentTimeJul 26th 2012
    Oh, I see I could not yet explain the model clear enough.

    The suggested four 'filters' are a classification which is
    orthogonal to all the other classifications now on the site,
    and have nothing to do with 'tags'. These are kept in unchanged

    Think of it as four SE threads which run like different kernels
    in a modern cpu in parallel. And there is a flag indicating
    which question is to be handled by which kernel.

    On the implementation level things are almost trivial: All one
    has to do is to add four bits to each question which indicates
    the kernel it should be run on.

    On the user interface side there would be an additional choice
    button for super users where they can indicate which of the four
    categories they think a question belongs to. The category itself will be
    computed by the system as, say, the median of the super user

    So you suggest that the filters would behave like different sites, on the same server that we can move questions between them... how would that be any different than migrating MO over to SE 2.0?


    Georg, your discussion seems to be bracketed by the assumption that certain software exists when it does not. You'd have to write the software that does what you want on your own since we don't have anything like it.

    That said, this is all too hypothetical.


    Whether or not it can practically be implemented, I have to say that Georg's idea has a certain appeal to me. It would give me a place to ask questions that I feel are probably above MSE level, but may not be well received on mathoverflow because of the expectation that questions should be "research level." It also might help to calibrate voting; a graduate-level question, and its answers, should receive more votes if asked as a graduate-level question than if asked as a research-level question.

    • CommentAuthorKaveh
    • CommentTimeJul 28th 2012 edited

    SE has a strong philosophical opposition to any kind of meta-tags (meta information about questions like their level, type, etc). The meta-tags are generally frowned upon. The idea of having meta-tags for categorizing question based on their level is very unlikely to be accepted. Even the homework tag has been quite contentious.

    The underlining issue is not particular to MO/MSE. There are users who want to have all of the questions they are interested and only those questions in one place, and the set of questions users are interested in varies a lot. SE's current solution is "tag sets" ( which allow filtering questions over the entire SE network based on sites and tags. Any improvement over that or any major modification of the software is unlikely to happen easily or any time soon. (They like the uniformity of their software over their entire network very much, it simplifies lots of things for them and the users.)

    ps: I personally like having separate sites (research vs. undergrad teaching) and I don't see any real benefit in merging them.

    What makes research people to be present on MSE not MO?
    Some questions that I've asked and seen on MO have run into criticism and even sarcasm. In contrast, I can be pretty sure that anything I might ask would be considered on-topic for MSE. So if I have doubts I post it there.

    I know that there are strong advocates for "keeping MO pure". I personally disagree with this view, but I respect it by posting semi-off-topic questions on MSE instead.
    Quote from

    "Asaf Karagila 18 hours ago

    I think that we forget that some of the people on MSE will be very against migration of advanced questions. I can come up with three or four of those people instantly. I will start a meta thread on meta.MSE to raise awareness of the upcoming issue (and it will rise...)."

    That is similar to my guess.

    So far the folks on meta.MSE are very much against migration.


    I suspect migration will mainly occur in the other direction: MO → MSE. Migration MSE → MO will most like happen when a question receives no useful replies on MSE, and there is some hope that MO participants will respond. I have reposted some of my own MSE questions for exactly this reason. An example is my question: Prime spiral distribution into quadrants.