793 research outputs found
Searching for superspreaders of information in real-world social media
A number of predictors have been suggested to detect the most influential
spreaders of information in online social media across various domains such as
Twitter or Facebook. In particular, degree, PageRank, k-core and other
centralities have been adopted to rank the spreading capability of users in
information dissemination media. So far, validation of the proposed predictors
has been done by simulating the spreading dynamics rather than following real
information flow in social networks. Consequently, only model-dependent
contradictory results have been achieved so far for the best predictor. Here,
we address this issue directly. We search for influential spreaders by
following the real spreading dynamics in a wide range of networks. We find that
the widely-used degree and PageRank fail in ranking users' influence. We find
that the best spreaders are consistently located in the k-core across
dissimilar social platforms such as Twitter, Facebook, Livejournal and
scientific publishing in the American Physical Society. Furthermore, when the
complete global network structure is unavailable, we find that the sum of the
nearest neighbors' degree is a reliable local proxy for user's influence. Our
analysis provides practical instructions for optimal design of strategies for
"viral" information dissemination in relevant applications.Comment: 12 pages, 7 figure
Theories for influencer identification in complex networks
In social and biological systems, the structural heterogeneity of interaction
networks gives rise to the emergence of a small set of influential nodes, or
influencers, in a series of dynamical processes. Although much smaller than the
entire network, these influencers were observed to be able to shape the
collective dynamics of large populations in different contexts. As such, the
successful identification of influencers should have profound implications in
various real-world spreading dynamics such as viral marketing, epidemic
outbreaks and cascading failure. In this chapter, we first summarize the
centrality-based approach in finding single influencers in complex networks,
and then discuss the more complicated problem of locating multiple influencers
from a collective point of view. Progress rooted in collective influence
theory, belief-propagation and computer science will be presented. Finally, we
present some applications of influencer identification in diverse real-world
systems, including online social platforms, scientific publication, brain
networks and socioeconomic systems.Comment: 24 pages, 6 figure
MCD: A Modified Community Diversity Approach for Detecting Influential Nodes in Social Networks
Over the last couple of decades, Social Networks have connected people on the
web from across the globe and have become a crucial part of our daily life.
These networks have also rapidly grown as platforms for propagating products,
ideas, and opinions to target a wider audience. This calls for the need to find
influential nodes in a network for a variety of reasons, including the curb of
misinformation being spread across the networks, advertising products
efficiently, finding prominent protein structures in biological networks, etc.
In this paper, we propose Modified Community Diversity (MCD), a novel method
for finding influential nodes in a network by exploiting community detection
and a modified community diversity approach. We extend the concept of community
diversity to a two-hop scenario. This helps us evaluate a node's possible
influence over a network more accurately and also avoids the selection of seed
nodes with an overlapping scope of influence. Experimental results verify that
MCD outperforms various other state-of-the-art approaches on eight datasets
cumulatively across three performance metrics.Comment: 18 pages 4 Figure
Spatial super-spreaders and super-susceptibles in human movement networks
As lockdowns and stay-at-home orders start to be lifted across the globe,
governments are struggling to establish effective and practical guidelines to
reopen their economies. In dense urban environments with people returning to
work and public transportation resuming full capacity, enforcing strict social
distancing measures will be extremely challenging, if not practically
impossible. Governments are thus paying close attention to particular locations
that may become the next cluster of disease spreading. Indeed, certain places,
like some people, can be "super-spreaders." Is a bustling train station in a
central business district more or less susceptible and vulnerable as compared
to teeming bus interchanges in the suburbs? Here, we propose a quantitative and
systematic framework to identify spatial super-spreaders and the novel concept
of super-susceptibles, i.e. respectively, places most likely to contribute to
disease spread or to people contracting it. Our proposed data-analytic
framework is based on the daily-aggregated ridership data of public transport
in Singapore. By constructing the directed and weighted human movement networks
and integrating human flow intensity with two neighborhood diversity metrics,
we are able to pinpoint super-spreader and super-susceptible locations. Our
results reveal that most super-spreaders are also super-susceptibles and that
counterintuitively, busy peripheral bus interchanges are riskier places than
crowded central train stations. Our analysis is based on data from Singapore,
but can be readily adapted and extended for any other major urban center. It
therefore serves as a useful framework for devising targeted and cost-effective
preventive measures for urban planning and epidemiological preparedness.Comment: 19 pages, 10 figure
Network centrality: an introduction
Centrality is a key property of complex networks that influences the behavior
of dynamical processes, like synchronization and epidemic spreading, and can
bring important information about the organization of complex systems, like our
brain and society. There are many metrics to quantify the node centrality in
networks. Here, we review the main centrality measures and discuss their main
features and limitations. The influence of network centrality on epidemic
spreading and synchronization is also pointed out in this chapter. Moreover, we
present the application of centrality measures to understand the function of
complex systems, including biological and cortical networks. Finally, we
discuss some perspectives and challenges to generalize centrality measures for
multilayer and temporal networks.Comment: Book Chapter in "From nonlinear dynamics to complex systems: A
Mathematical modeling approach" by Springe
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