Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A representation problem for smooth sums of ridge functions   In this paper we prove that if a multivariate function of a certain
smoothness class is represented by a sum of $k$ arbitrarily behaved ridge
functions, then it can be represented by a sum of $k$ ridge functions of the
same smoothness class and a polynomial of degree at most $k-1$. This solves the
problem posed by A. Pinkus in his monograph "Ridge Functions" up to a
multivariate polynomial.

19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
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The categories of this paper are: stat
8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an