Another comment on MSC: while I'm happy that this classification of mathematical content exists, it seems to me that in graph theory it is not sufficiently deep (and also misses some topics). That's the reason why we chose to create a different subject tree. And partially it's also the reason why we hesitate to create new categories in areas outside our field of expertize: we would like to have a classification scheme that makes sense to people working in any particular area: and we can't easily judge this. Also, some fields may be more active than others (or have more problems that are easy to explain), and this should possibly be also taken into account.

However, if you (or anyone) has a concrete suggestion, we welcome any ideas.

Hi DOT,

Well, I don't think you need to worry about your popularity here.. and further, I don't see how your post could hurt it.

With the Garden in general and the subject tree in particular, we are trying to make practical choices which make our site as easy to use as possible. While I agree that there would be some usability benefits to following the MSC classification, I don't think this would be a good choice for us. First off, I think the benefits would be slim.. my feeling is that our subject tree is already pretty easy to navigate. More significantly, following the MSC would force us to use a tree which would require a 4th level and would surely be even more unbalanced in terms of content (and thus harder to navigate). I think the downside of a more unbalanced tree would outweigh the upside of the MSC classification, but I would be happy to hear what other users have to say about this.

As far as the present bias of our site toward discrete math and graph theory is concerned, this is very much something I would like to see change. If creating new topics and subtopics would lead to people actually posting problems, I would do this pronto. Do you think this would help?