Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: STG2Seq: Spatial-temporal Graph to Sequence Model for Multi-step
  Passenger Demand Forecasting
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
3
The categories of this paper are: physics
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg