11 research outputs found
Adversarial Attack on Community Detection by Hiding Individuals
It has been demonstrated that adversarial graphs, i.e., graphs with
imperceptible perturbations added, can cause deep graph models to fail on
node/graph classification tasks. In this paper, we extend adversarial graphs to
the problem of community detection which is much more difficult. We focus on
black-box attack and aim to hide targeted individuals from the detection of
deep graph community detection models, which has many applications in
real-world scenarios, for example, protecting personal privacy in social
networks and understanding camouflage patterns in transaction networks. We
propose an iterative learning framework that takes turns to update two modules:
one working as the constrained graph generator and the other as the surrogate
community detection model. We also find that the adversarial graphs generated
by our method can be transferred to other learning based community detection
models.Comment: In Proceedings of The Web Conference 2020, April 20-24, 2020, Taipei,
Taiwan. 11 page
Network Members Can Hide from Group Centrality Measures
Group centrality measures are a generalization of standard centrality,
designed to quantify the importance of not just a single node (as is the case
with standard measures) but rather that of a group of nodes. Some nodes may
have an incentive to evade such measures, i.e., to hide their actual
importance, in order to conceal their true role in the network. A number of
studies have been proposed in the literature to understand how nodes can rewire
the network in order to evade standard centrality, but no study has focused on
group centrality to date. We close this gap by analyzing four group centrality
measures: degree, closeness, betweenness, and GED-walk. We show that an optimal
way to rewire the network can be computed efficiently given the former measure,
but the problem is NP-complete given closeness and betweenness. Moreover, we
empirically evaluate a number of hiding strategies, and show that an optimal
way to hide from degree group centrality is also effective in practice against
the other measures. Altogether, our results suggest that it is possible to hide
from group centrality measures based solely on the local information available
to the group members about the network topology