Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Effect of Use and Access on Citations   It has been shown (S. Lawrence, 2001, Nature, 411, 521) that journal articles
which have been posted without charge on the internet are more heavily cited
than those which have not been. Using data from the NASA Astrophysics Data
System (ads.harvard.edu) and from the ArXiv e-print archive at Cornell
University (arXiv.org) we examine the causes of this effect.

0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
16
The categories of this paper are: stat
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math