Università della Svizzera italiana
Department of Economics
Title: From ties to events in the analysis of social and other kinds of networks
Abstract: When networks of social relations evolve at a slower pace than directed individual behavior, social networks can be considered as sets of exogenous relational states (e.g., friendship networks and telephone calls). When networks of social relations evolve on a time scale comparable with that of directed individual behavior (e.g., on/off-line conversation and emotional contagion), social networks become endogenous to - and may co-evolve with behavior. In both cases social networks may be usefully represented as mutually exclusive edge states (present, absent) defined over appropriate time intervals. This representation of social networks becomes increasingly problematic as directed individual behavior evolves over progressively shorter time spells (e.g., financial transactions, radio communications). In the limit, when the duration of time spells tends to zero, what remains are observations of sequences of instantaneous, non-simultaneous events. During the last fifteen years, a major line of network research has been developed to study the network properties of these relational event sequences. In this talk, I provide examples taken from my own empirical research to illustrate and review the accomplishments, problems, and promises of this recent line of research on the dynamics of social and other kinds of networks.
Autonomous University of Barcelona, Spain
Kozminski University, Warsaw, Poland
Title: A handful of friends or a hundred acquaintances?
Abstract: Social scientists have long analyzed personal networks to understand human interaction, social support, cohesion, and inclusion (e.g., Fischer, 1982; Wellman, 1979). Nevertheless, we focus predominantly on individuals’ core networks. Thus, the hundreds of more superficial or weak ties an individual has are habitually ignored - ties with, for instance, neighbors, colleagues, other parents at children’s schools, fellow members of associations or religious congregations, or social media contacts (acquaintances; Goffman, 1963; Morgan, 2009). In this talk, I argue why analyzing how acquaintanceship networks are composed and structured, how they differ across social groups, how they are mobilized, and how they affect individuals and societies should be a core task of the social scientific enterprise. I also propose a novel methodology and a research agenda for studying broad acquaintanceship networks.
Davide Vega D'Aurelio
Department of Information Technology
Title: Beyond communities: a quest to identify online conversations
Abstract: Community detection methods are commonly used to study social networks, but they may not be suitable for analyzing online social media. This talk argues that detecting online conversations is a more sensitive and meaningful approach to studying complex networks. However, unlike in a face-to-face situation, where we can fairly recognize which conversations are co-occurring around us and who their participants are, automatically identifying cohesive conversations online can be challenging due to the abundance of noise, lack of context, and diversity of interactions. Rather than providing direct answers to these challenges, the talk will explore the difficulties and limitations of detecting conversations.