Matthew Brashears of Cornell University will present the following talk at Northeastern on Thursday, September 18 at noon in 540 Holmes Hall.


Social Networks, Compression Heuristics, and the Evolution of Human Intelligence
Matthew Brashears, Cornell University
12pm on September 18, 2014 (a light lunch will be served)
540 Holmes, Northeastern University
The ability of primates, including humans, to maintain large social networks appears to depend on the ratio of the neocortex to the rest of the brain. However, observed human network size frequently exceeds predictions based on this ratio (e.g., “Dunbar’s Number”), implying that human networks are too large to be cognitively managed. I argue that humans adaptively use compression heuristics to allow larger amounts of social information to be stored in the same brain volume. I find that human adults can remember larger numbers of relationships in greater detail when a network exhibits triadic closure and kin labels than when it does not. In an extension of this line of research, a second study investigates whether differences in male and female networks derive partly from different strategies for encoding network information. I find that while gender impacts social network recall, being made aware of one’s gender identity does not, suggesting that differences in male and female networks may be partly due to sex-based differences in network cognition.
Matthew E. Brashears earned his Ph.D. in Sociology from the University of Arizona in 2008 and is presently an Assistant Professor of Sociology at Cornell University. He is primarily interested in social networks, with particular emphasis on the links between networks and social psychology. His current research focuses on linking cognition to social network structure, studying the effects of error and error correction on diffusion dynamics, and using ecological models to connect individual behavior to collective dynamics. He is also interested in the estimation of ego network size and composition, as well as in covert social networks. He is sole P.I. on three funded research projects. The first, supported by the National Science Foundation, explores how our cognitive assets and liabilities shape social network structure. The second, supported by the Defense Threat Reduction Agency, is developing new methods for identifying terrorist groups preparing chemical, biological, radiological, and nuclear (CBRN) attacks. The third, supported by a Short-Term Innovative Research (STIR) award from the Army Research Office, is using a new experimental design to study how innovation emerges from efforts to imitate, and how network structure influences this process.  His work has appeared in Nature Scientific Reports, the American Sociological Review, Social Networks, Sociological Science, and Social Psychology Quarterly, among others. He recently finished a term as an officer for the ASA Mathematical Sociology section, and currently serves on the editorial board for Social Psychology Quarterly.