Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Coping with area price risk in electricity markets: Forecasting
  Contracts for Difference in the Nordic power market
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an