Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Prisoner's Dilemma on Graphs with Large Girth   We study the evolution of cooperation in populations where individuals play
prisoner's dilemma on a network. Every node of the network corresponds on an
individual choosing whether to cooperate or defect in a repeated game. The
players revise their actions by imitating those neighbors who have higher
payoffs. We show that when the interactions take place on graphs with large
girth, cooperation is more likely to emerge. On the flip side, in graphs with
many cycles of length 3 and 4, defection spreads more rapidly. One of the key
ideas of our analysis is that our dynamics can be seen as a perturbation of the
voter model. We write the transition kernel of the corresponding Markov chain
in terms of the pairwise correlations in the voter model. We analyze the
pairwise correlation and show that in graphs with relatively large girth,
cooperators cluster and help each other.

17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
19
The categories of this paper are: eess
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
18
The categories of this paper are: econ