Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Experimental Identification of Hard Data Sets for Classification and
  Feature Selection Methods with Insights on Method Selection
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
17
The categories of this paper are: q-fin