Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Note on Affine Invariant Cost Functions   We show that any affine invariant function on the set of positive definite
matrices must factor through the determinant function, as long as the
restriction of the function to scalar matrices is surjective. A motivation from
robust statistics is discussed.

25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
1
The categories of this paper are: cs