Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effects of fractional derivatives in epidemic models   We study epidemic Susceptible-Infected-Susceptible models in the fractional
setting. The novelty is to consider models in which the susceptible and
infected populations evolve according to different fractional orders. We study
a model based on Caputo derivative, for which we establish existence results of
the solutions. Also, we investigate a model based on Caputo-Fabrizio operator,
for which we provide existence of solutions and a study of the equilibria.
Numerical simulations for both models and a direct numerical comparison are
also provided.

12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn