Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Searching for polarization in signed graphs: a local spectral approach   Signed graphs have been used to model interactions in social net-works, which
can be either positive (friendly) or negative (antagonistic). The model has
been used to study polarization and other related phenomena in social networks,
which can be harmful to the process of democratic deliberation in our society.
An interesting and challenging task in this application domain is to detect
polarized communities in signed graphs. A number of different methods have been
proposed for this task. However, existing approaches aim at finding globally
optimal solutions. Instead, in this paper we are interested in finding
polarized communities that are related to a small set of seed nodes provided as
input. Seed nodes may consist of two sets, which constitute the two sides of a
polarized structure.
  In this paper we formulate the problem of finding local polarized communities
in signed graphs as a locally-biased eigen-problem. By viewing the eigenvector
associated with the smallest eigenvalue of the Laplacian matrix as the solution
of a constrained optimization problem, we are able to incorporate the local
information as an additional constraint. In addition, we show that the
locally-biased vector can be used to find communities with approximation
guarantee with respect to a local analogue of the Cheeger constant on signed
graphs. By exploiting the sparsity in the input graph, an indicator vector for
the polarized communities can be found in time linear to the graph size.
  Our experiments on real-world networks validate the proposed algorithm and
demonstrate its usefulness in finding local structures in this semi-supervised
manner.

28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex