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    • CommentRowNumber1.
    • CommentAuthorAndrew Stacey
    • CommentTimeJun 22nd 2010

    counterexamples in algebra inspired (and largely copied from) this MO question since MO is a daft place to put that stuff and a page on the nLab seems better. (A properly indexed database would be even better, but I don’t feel like setting such up and don’t know of the existence of such a system)

    • CommentRowNumber2.
    • CommentAuthorTim_van_Beek
    • CommentTimeJun 22nd 2010

    Has anyone suggested to the MO folks that they could add this to Wikipedia, or maybe to a MO owned Wiki, if they think they need another layer of indirection? Sooner or later the question-answer structure won’t be very useful anymore as a basis for a data warehouse…

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeJun 22nd 2010
    • (edited Jun 22nd 2010)

    I edited the entry a bit:

    • fixed the toc command

    • moved the attribution to MO to a References-section

    • linked to it from algebra

    • added plenty of hyperlinks

    (A properly indexed database would be even better,

    I can’t quite imagine that a format other than a Wiki would be better suited to host such things. All one would really want to do now is take every single item of the “counterexamples”-entry and copy it into the Examples-section of the entry that explains the corresponding term.

    • CommentRowNumber4.
    • CommentAuthorAndrew Stacey
    • CommentTimeJun 22nd 2010

    Thanks, Urs! That looks much nicer. It was when I came across the third spelling of “Noetherian” that I realised that I was a bit out of my depth with the hyperlinking. And not being an algebraist, I wasn’t sure what should and shouldn’t be linked. Just need to fix that multiplication table …

    Tim, do you think that this should not be on the nLab? Or is your point a bit more general - that MO should have a spin-off wiki of its very own?

    I think that a page like this could be a bit of a recruitment page for us, since it’s a very easy one for a newcomer to add to. And whilst I wouldn’t just copy out Counterexamples in Topology then I would quite like to do so!

    • CommentRowNumber5.
    • CommentAuthorAndrew Stacey
    • CommentTimeJun 22nd 2010

    Just thought of one reasonably easy way to do the copying: make each subsection of the counterexamples page a separate page. Then the main page includes all the subpages, and each subject page includes its relevant counterexample page.

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeJun 22nd 2010

    and each subject page includes its relevant counterexample page.

    You mean by the include-command?

    That would be a possibility. But we could also directly type the material into the corresponding subject page.

    All we seem to need is to extend the practice of having an Examples-section in each entry to having also (at least sometimes) a Counterexamples-section,

    • CommentRowNumber7.
    • CommentAuthorTim_van_Beek
    • CommentTimeJun 22nd 2010

    Tim, do you think that this should not be on the nLab? Or is your point a bit more general - that MO should have a spin-off wiki of its very own?

    The latter, wikipedia may be to restrictive or intimidating - the nLab community is too small to handle all the content of MO, but I can imagine that one could create a spin-off wiki for MO and remind all authors of questions to add any useful answers to that, as a kind of compensation for the help they got.

    A properly indexed database would be even better, but I don’t feel like setting such up and don’t know of the existence of such a system.

    When I hear “database” I think of a relational database like Oracle or MySQL, or maybe an object oriented database, but that’s not what you are thinking of, are you?

    • CommentRowNumber8.
    • CommentAuthorUrs
    • CommentTimeJun 22nd 2010

    the nLab community is too small to handle all the content of MO,

    Why is that? The nLab community is as large or small as there are peple who add content to it.

    I think it is unlikely that MO users will flood the nLab with moving over content. But some of them migh start doing so, and I think that would be very useful, not the least for MO itself.

    I had suggested this from the very beginning, that a discussion-site such as MO is most useful if it tries to store stable and worthwhile outcome of discussions in a wiki, such as the nLab. But at some point I stopped making that suggestion, since I wasn’t really getting positive feedback.

    • CommentRowNumber9.
    • CommentAuthorAndrew Stacey
    • CommentTimeJun 22nd 2010

    I don’t think that there will be any great support for an MO-wiki. I don’t think that the majority of MO questions fit into a wiki-format. Rather, one starts writing something, finds a minor niggle, asks a question, then fits the answer back in to the original document. So the place to get people is in writing that original document. Asking people to add the answer to a wiki means that they have to reformulate the question and answer and to do it right takes us beyond cut-and-paste.

    However, every now and then a question like this one comes along which would make more sense on a wiki and would work with everyone just adding little bits. That’s when we can make the case for the nLab by demonstration. They key word here is symbiosis: both parties benefiting from their interaction.

    • CommentRowNumber10.
    • CommentAuthorTim_van_Beek
    • CommentTimeJun 22nd 2010

    Why is that? The nLab community is as large or small as there are peple who add content to it.

    It’s just my impression that there are more active contributors to MO right now that there are for the nLab, that’s all.

    But at some point I stopped making that suggestion, since I wasn’t really getting positive feedback.

    Probably because Andrew is right with #9.

    • CommentRowNumber11.
    • CommentAuthorUrs
    • CommentTimeJun 22nd 2010

    It’s just my impression that there are more active contributors to MO right now that there are for the nLab, that’s all.

    Sure, but is the implication of this that MO content cannot be filled into the nLab? I don’t think so. If more people start doing so, by definition the “community” who does so increases.

    My point is just that I find it premature to say that certain things the nLab cannot be used for, before trying.

    • CommentRowNumber12.
    • CommentAuthorUrs
    • CommentTimeJun 22nd 2010

    But at some point I stopped making that suggestion, since I wasn’t really getting positive feedback.

    Probably because Andrew is right with #9.

    No, I don’t think so. I think many questions and answers that are exchanged on MO deserve to be archived in robust form in a Wiki. I never posted a reply to MO that I hadn’t essentially previously typed out here.

    No, I still think it would be good, but that it is hard to make people see it. Even here! :-)

    • CommentRowNumber13.
    • CommentAuthorHarry Gindi
    • CommentTimeJun 22nd 2010

    I feel like the amount of (oo,1)-stuff on most pages scares away some of the people on MO. This has definitely gotten better since a few months ago, since it seems like there’s been a pretty active effort to split the ordinary and the (oo,1) pages into separate parts.

    • CommentRowNumber14.
    • CommentAuthorTodd_Trimble
    • CommentTimeJun 22nd 2010

    Aside from Andrew’s #9, my guess is that a lot of people are on some level intimidated by the Lab, thinking that entries have to be in a certain nPOV style or something. Of course that’s rubbish to people on the inside.

    If some exchange at MO looks worth recording here, it might be good for someone to do so in rough form and drop a comment at MO saying that a new Lab entry has been created based on the exchange. It could be that we gradually teach consumers at MO how things really work here in reality.

    • CommentRowNumber15.
    • CommentAuthorUrs
    • CommentTimeJun 22nd 2010

    I feel like the amount of (oo,1)-stuff on most pages scares away some of the people on MO.

    We had these same discussions right after the nLab was created, when there was no (oo,1)-content. No, I don’t think that’s the reason.

    I knew this was going to happen: first people thought up 1001 reasons why they would rather not contribute to the nLab. Then only a handful of people did add content. Now there is the 1002nd reason not to: it’s because the content that is present is just of small scope by a small number of people.

    It’s circular and a bit weird. And I don’t think any of this is actually the reason.

    • CommentRowNumber16.
    • CommentAuthorAndrew Stacey
    • CommentTimeJun 22nd 2010

    Whilst I think it is important to think of ways to encourage more people to join the nLab, and indeed part of my thought behind starting the “counterexamples” page was to do that, I’d like to state one thing at the outset:

    I don’t care if no-one else contributes to the nLab.

    That’s perhaps a bit strong. What I mean by that is that the nLab is useful to me right now and with the current set of contributors. Indeed, it’s useful to me with no other contributors. It is certainly true that the more contributors it has, then the more useful it is (presumably up to some limit), but I’d like to ensure that discussions like this start from the position “We’ve got this great tool and we’d like to tell others about it” rather than bemoaning the fact that not more people join in!

    • CommentRowNumber17.
    • CommentAuthorUrs
    • CommentTimeJun 22nd 2010

    Very true. And I stopped bemoaning it long ago, after my first surprise was over.

    What however I still do is point out that many of the reasons that are brought forward for why people allegedly cannot add to the nLab, such as voiced above, are no real reasons.

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