Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The apparent Fermi liquid concept helps to understand thermoelectric
  materials   Invited expert opinion on the article S. Kremer and R. Fresard, Ann. Phys.
(Berlin) 524, 21 (2012).

16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin