Yoshimichi Sato is professor of sociology at the Faculty of Psychology, Kyoto University of Advanced Science. His research areas in sociology include the study of social capital, social inequality, and theories of social change. He applies game theory, agent-based models, and statistical models to these topics. He has been active in the international arena. He was a visiting scholar at the University of Chicago and Cornell University and served as a chair of Session on Rationality and Society of the American Sociological Association and as a president of Research Committee 45 (Rational Choice) and an executive committee member of the International Sociological Association. He was a co-editor of Sociology Section of International Encyclopedia of Social and Behavioral Sciences, 2nd Edition, which received PROSW awards in 2016. Hiroki Takikawa is an Associate Professor at Graduate School of Humanities and Sociology, the University of Tokyo, Japan. He earned his PhD andBA in Sociology from the University of Tokyo. His research area includes mathematical sociology, social network analysis, and computational social science. He is currently studying the mechanism of social division and political polarization through large-scale data analysis. His research has been published in academic journals including PLOS ONE, Quality and Quantity and conferences proceedings such as IEEE Big data.