Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comparing the hierarchy of author given tags and repository given tags
  in a large document archive   Folksonomies - large databases arising from collaborative tagging of items by
independent users - are becoming an increasingly important way of categorizing
information. In these systems users can tag items with free words, resulting in
a tripartite item-tag-user network. Although there are no prescribed relations
between tags, the way users think about the different categories presumably has
some built in hierarchy, in which more special concepts are descendants of some
more general categories. Several applications would benefit from the knowledge
of this hierarchy. Here we apply a recent method to check the differences and
similarities of hierarchies resulting from tags given by independent
individuals and from tags given by a centrally managed repository system. The
results from out method showed substantial differences between the lower part
of the hierarchies, and in contrast, a relatively high similarity at the top of
the hierarchies.

19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con