Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Seeing through the smoke : a world-wide comparative study of e-cigarette
  flavors, brands and markets using data from Reddit and Twitter   The growing popularity of E-cigarettes, an alternative to cigarettes, has
motivated us to study trends of the brands, flavors and online market activity
using posts from Reddit and Twitter. The main motivation for this world-wide
study is to emphasize the difference that laws and regulations have on the
usage and availability of different flavors and brands of vapes in different
countries. Data has been obtained from subreddits belonging to e-cigarette
communities from Australia, Canada, Europe, and the UK. Extensive cleaning of
data, and rigorous text mining operations provide varying results for different
countries. Varying results have been obtained from Reddit and Twitter since
they provide different atmospheres to the users.

12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th