73,181 research outputs found
Dominating sets and ego-centered decompositions in social networks
Our aim here is to address the problem of decomposing a whole network into a
minimal number of ego-centered subnetworks. For this purpose, the network egos
are picked out as the members of a minimum dominating set of the network.
However, to find such an efficient dominating ego-centered construction, we
need to be able to detect all the minimum dominating sets and to compare all
the corresponding dominating ego-centered decompositions of the network. To
find all the minimum dominating sets of the network, we are developing a
computational heuristic, which is based on the partition of the set of nodes of
a graph into three subsets, the always dominant vertices, the possible dominant
vertices and the never dominant vertices, when the domination number of the
network is known. To compare the ensuing dominating ego-centered decompositions
of the network, we are introducing a number of structural measures that count
the number of nodes and links inside and across the ego-centered subnetworks.
Furthermore, we are applying the techniques of graph domination and
ego=centered decomposition for six empirical social networks.Comment: 17 pages, 7 figure
From Social Data Mining to Forecasting Socio-Economic Crisis
Socio-economic data mining has a great potential in terms of gaining a better
understanding of problems that our economy and society are facing, such as
financial instability, shortages of resources, or conflicts. Without
large-scale data mining, progress in these areas seems hard or impossible.
Therefore, a suitable, distributed data mining infrastructure and research
centers should be built in Europe. It also appears appropriate to build a
network of Crisis Observatories. They can be imagined as laboratories devoted
to the gathering and processing of enormous volumes of data on both natural
systems such as the Earth and its ecosystem, as well as on human
techno-socio-economic systems, so as to gain early warnings of impending
events. Reality mining provides the chance to adapt more quickly and more
accurately to changing situations. Further opportunities arise by individually
customized services, which however should be provided in a privacy-respecting
way. This requires the development of novel ICT (such as a self- organizing
Web), but most likely new legal regulations and suitable institutions as well.
As long as such regulations are lacking on a world-wide scale, it is in the
public interest that scientists explore what can be done with the huge data
available. Big data do have the potential to change or even threaten democratic
societies. The same applies to sudden and large-scale failures of ICT systems.
Therefore, dealing with data must be done with a large degree of responsibility
and care. Self-interests of individuals, companies or institutions have limits,
where the public interest is affected, and public interest is not a sufficient
justification to violate human rights of individuals. Privacy is a high good,
as confidentiality is, and damaging it would have serious side effects for
society.Comment: 65 pages, 1 figure, Visioneer White Paper, see
http://www.visioneer.ethz.c
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