Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Click Through Rate Prediction for Contextual Advertisment Using Linear
  Regression
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ