Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Tuning Parameter Selection in Regularized Estimations of Large
  Covariance Matrices
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph