Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Understanding the faint red galaxy population using large-scale
  clustering measurements from SDSS DR7
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph