Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Multi-Level Micro-Randomized Trial: Detecting the Proximal Effect of
  Messages on Physical Activity
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th