Title: Latent variable modelling of interdependent ego-networks
Authors: Isabella Gollini - Birkbeck, University of London (United Kingdom)
Alberto Caimo - Dublin Institute of Technology (Ireland)
Paolo Campana - University of Cambridge (United Kingdom)
Isabella Gollini - University College Dublin (Ireland) [presenting]
Abstract: Ego-networks consist of a focal node (``ego'') and the nodes to whom ego is directly connected to (``alters''). We present a Bayesian latent variable network modelling framework for describing the connectivity structure of interdependent ego-networks (network of ego-networks) by using a latent space approach. This allows us to visualise both the ego-ego and ego-alter relational structures by estimating the positions of all the individuals in a latent ``social space''. We apply this new methodology using an efficient variational algorithm able to explore the structure of human smuggling network out of Libya (operation Glauco II) consisting of ego-networks based on the wiretaps acquired by the Italian police on 29 suspects during an investigation period lasting from January to October 2014. The statistical challenge with these ego-networks is that the large number of alters (more than 15k people) can potentially be members of several ego-nets.