How to get started with p*/ERGM

What’s all this about p*/ERGM? So you’ve just experienced Prof. Noshir Contractor’s keynote, and he was all over this new-fangled technique for the statistical modeling of social networks, and you’ve never heard of it. Curious? Try one of these articles from our collaborators, generally acknowledged as excellent starting points:

Read both – a slight edge to Robins, Pattison, Kalish and Lusher on the strength of their Figures which may elicit a genuine “Ah, ha!” moment, while the worked examples in Anderson, Wasserman, and Crouch are more substantial.

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Yuval Kalish Workshop

Yuval Kalish, an assistant professor in the Department of Management of Tel Aviv University will be leading a workshop on Wednesday, September 14 from 2:00-5:30 pm in Frances Searle, Room 1.459.
This workshop provides a hands-on tutorial on how to fit Exponential Random Graph (ERG) Models for social selection using Pnet.

If you plan on attending, please RSVP to Marilyn Logan by 5pm September 13.

ERG models have been referred to as the most promising technique for the modeling of social networks (Snijders, 2007), and has wide applications in the area of organizational studies and communication studies. Topics include: the logic of ERG models, Parameter selection and estimation, parameter interpretation, Goodness of Fit, and troubleshooting convergence issues.
We will discuss Multivariate ERG models if time permits and there is participant interest. Participants are requested to bring their laptops after they have downloaded pnet from: and made sure that it works on their computer.

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Yuval Kalish SONIC Speaker Series

Visiting scholar Yuval Kalish will be presenting “Till Stress Do Us Part: Linking Communication networks, Stress and Voluntary Exit in Extreme Contexts”  on Monday, August 29, 2011 10:30-11:30 a.m.

Research has linked stress with various withdrawal behaviors, including voluntary exit from groups. research also demonstrated that stress is contagious – it spreads among group members. However, there is no detailed theory or study of the mechanisms by which stress is disseminated by individuals to others in a group. We discuss and empirically test four stress-related processes that explain why some individuals voluntarily leave their group.

Two hundred and seventy-eight individuals (17 groups) in a unique military setting were measured for their communication-network structure and individual stress at three time-points. Using HLM and stochastic actor-oriented models for social networks, we found support for stress-related withdrawal and selection, and for stress-contagion. Managerial implications are discussed.

Yuval Kalish is assistant professor at the Department of Management, Tel Aviv University. His research focuses on the relationship between individual attributes, networks structures and outcomes within and between organizations. He focuses on the modeling of social networks using Exponential Random Graph models (for which he jointly received the most cited paper award in Social Networks) and other analytic techniques. He teaches courses on leadership, conflict management, statistics and network analysis.

Download the flyer here.


Till Stress Do Us Part


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Gold farming conference acceptances

The VWO gold farming team has had several papers accepted for presentation at upcoming conferences.

Keegan, B., Ahmad, M., Williams, D., Srivastava, J., Contractor, N. (2011). “Mapping Gold Farming Back to Offline Clandestine Organizations: Methodological, Theoretical, and Ethical Challenges.” Game Behind the Video Game, Rutgers University, New Brunswick, NJ.

Keegan, B., Ahmad, M., Williams, D., Srivastava, J., Contractor, N. (2011). “Title: Using ERGMs to Map Online Clandestine Behavior to Offline Criminal Activity.” International Network of Social Network Analysis, Sunbelt XXXI, Tampa, FL.

See this and other VWO-related information at the project website.

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