Prof. Matthew Jackson Lectures on Social Capital’s Impact on Inequality and Immobility
Aug 20-2024
Upon the invitation of the NSD, Prof. Matthew Jackson, former chairman of the Game Theory Society, gave a lecture entitled ‘Social Capital in Determining Patterns of Inequality and Immobility’ on August 16, 2024. It preceded the 7th World Congress of the Game Theory Society, held at the NSD from August 19 to 22. The lecture was part of a year-long series commemorating the 30th anniversary of the establishment of the NSD. Xing Yiqing, NSD Tenured Associate Professor, hosted the event.
Matthew Jackson is Professor of Economics at Stanford University, a member of the National Academy of Sciences, a fellow of the American Academy of Arts and Sciences, a member of the American Association for the Advancement of Science, and a fellow of the Econometric Society. He has served as editor or co-editor of leading journals such as Econometrica and PNAS. Credited as the founder of the study of social and economic networks, he has published many books, including ‘The Human Network' and `Social and Economic Networks'.
In his lecture at the NSD, Prof. Jackson introduced his research on the relationships between social capital and mobility. He began by setting forth the definitions of inequality and immobility, with the former focusing on the income and wealth disparities among individuals and the latter stressing the connections between children’s development and their parents’ status. Based on the data of 72 million Facebook users, Prof. Jackson delved into the impact of various types of social capital on economic mobility, including connectedness, cohesiveness, and civic engagement. Economic connectedness (or homophily), a metric for measuring the ratio of high socioeconomic status (SES) friends to an individual’s total friends, displayed a conspicuous positive correlation with his or her upward economic mobility. Statistics across the US corroborated this finding, said Prof. Jackson.
He expounded on the mechanism for such an influence by dissecting the ways economic connectedness impacted on individuals in social networks. Firstly, referrals through connections confer job-seeking advantage, which he demonstrated through a concise ‘overlap’ model. In addition, an individual’s behavior or norm can be influenced by companions through connectedness, or he or she can obtain more information from friends.
Social capital could be improved through various methods, including algorithmic fairness, affirmative action, or social engineering, he said. However, he pointed out that each carried certain risk. His research with collaborators at Caltech showed that homophily might generate positive influence. Moreover, altering social network structures tend to have unexpected consequences. His research on loan-giving in Indian villages found that a tweak to part of a network bore on the rest of it.
