Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Model for the growth of the World Airline Network   We propose a probabilistic growth model for transport networks which employs
a balance between popularity of nodes and the physical distance between nodes.
By comparing the degree of each node in the model network and the WAN, we
observe that the difference between the two is minimized for $\alpha\approx 2$.
Interestingly, this is the value obtained for the node-node correlation
function in the WAN. This suggests that our model explains quite well the
growth of airline networks.

36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con