Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Stochastic lattice gas model describing the dynamics of an epidemic   We study a stochastic process describing the onset of spreading dynamics of
an epidemic in a population composed by individuals of three classes:
susceptible (S), infected (I), and recovered (R). The stochastic process is
defined by local rules and involves the following cyclic process:
S$\to$I$\to$R$\to$S (SIRS). The open process S$\to$I$\to$R (SIR) is studied as
a particular case of the SIRS process. The epidemic process is analyzed at
different levels of description: by a stochastic lattice gas model and by a
birth and death process. By means of Monte Carlo simulations and dynamical
mean-field approximations we show that the SIRS stochastic lattice gas model
exhibit a line of critical points separating two phases: an absorbing phase
where the lattice is completely full of S individuals and an active phase where
S, I and R individuals coexist, which may or may not present population cycles.
The critical line, that corresponds to the onset of epidemic spreading, is
shown to belong in the directed percolation universality class. By considering
the birth and death process we analyse the role of noise in stabilizing the
oscillations.

26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs