---------- Forwarded message ---------- Date: Fri, 29 Jun 2012 17:18:18 +0530 From: Athif Mohammed <athif@isim.ac.in> Description: Description: isim_NEW_logo Project Colloquium On "Mining Locality-Preserving Trust Hierarchies in Signed Networks" By Ms. Mili Ann Abraham 2nd year M.Tech Student International School of Information Management University of Mysore, Mysore Date and Time: 12 PM, Saturday, June 30, 2012 Supervisor: Prof. Mandar R Mutalikdesai Member Technical Staff - Corporate Research and Technologies Siemens Technology and Services Private Limited Bangalore You are cordially invited Dr.Shalini R Urs Executive Director and Professor International School of Information Management University of Mysore, Mysore Abstract The phenomena of social hierarchy and stratification among humans could be traced back to the origin of human society. Presently, the growing popularity of online social networks has provided an opportunity to analyze these well-studied phenomena over different networks at different scales. Generally, a social network can be considered as a collection of actors and their interactions (connections). In signed networks, there is an explicit show of trust (positive) or distrust (negative) among the actors. That is, an actor can designate others as friends or foes. Examples of signed networks include the Slashdot Zoo network, Epinions etc. In a social network, actors tend to connect with each other on the basis of their perceived social hierarchy. The concept of social hierarchy can be stated as the emergence of a tree-like structure comprising of actors in a top-down fashion in the order of their ranks, describing a specific parent-child relationship, viz. child trusts parent. However, owing to the presence of positive as well as negative interactions in signed networks, deriving trust hierarchies is a non-trivial challenge. We argue that traditional notions are insufficient to derive hierarchies underlying signed networks. To build hierarchies in signed networks, we introduce two interpretations of trust/goodness namely 'presence of trust (good)' and 'lack of distrust (not bad)'. In order to develop a hierarchy signifying both trust and distrust more effectively, the above interpretations are combined and the actors are arranged according to their aggregate deserve (trust) values. We then introduce a hypothesis for building hierarchies based on deserve values while preserving the locality of interactions between actors. In this sense, even though a hierarchy represents an aggregate social structure, the relationships are formed from local structures. The hierarchies obtained using our hypothesis are said to be locality-preserving, with each hierarchy representing a well-defined local community. Each such hierarchy contains a community representative at the root. Modeling such locality-preserving hierarchies in trust networks finds applications in community detection, information dissemination and locality-based governance for the population. For further details visit <http://www.isim.ac.in> www.isim.ac.in INTERNATIONAL SCHOOL OF INFORMATION MANAGEMENT University of Mysore, Manasagangotri, Mysore -570006 Ph: +91-821-2514699 | Fax: +91-821-2519209 | <mailto:office@isim.ac.in> office@isim.ac.in Athif Mohammed Assistant Manager International School of Information Management (ISiM) University of Mysore, Manasagangotri, Mysore - 570006. Email- office@isim.ac.in M: +91 9886772356 Website: www.isim.ac.in