Group Consequences of Individual Strategies

I recently received this fascinating summary of an upcoming lecture* by Robert Goldstone of Indiana University:

Just as ants interact to form elaborate colonies and neurons interact to create structured thought, groups of people interact to create emergent organizations that the individuals may not understand or even perceive. To study the emergence of group behavior patterns, we have developed an internet-based experimental platform (for examples, see ) that allows groups of 2-200 people to interact with each other in real time on networked computers. Using these technologies, I will describe experiments on how innovations are propagated within a group. One series of experiments explores how people attempt to solve simple problems while taking advantage of the developing solutions of other people in their social network. The results suggest that complete information is not always beneficial for a group, and that problem spaces requiring substantial exploration benefit from networks with mostly locally connected individuals.

In a second line of experiments, we study the dissemination of innovations in a networked group for a multi-dimensional search problem with many local minima. We find evidence for several strategies that determine imitation and innovation decisions based on: similarity, choice popularity, timing, and success.

In a third, real-world application area, I consider historical data on how U.S. parents name their children. We find that naming choices are influenced by both the frequency of a name in the general population, and by its “momentum” in the recent past in the sense that names which are growing in popularity are preferentially chosen. This momentum bias has itself been increasing over the course of 130 years. For each of these areas, I will describe agent-based modeling efforts at explaining empirically observed patterns of exploration and exploitation, bandwagon effects, population waves, and compromises between individuals using their own information and information obtained from their peers.

*Featured speaker at at the 20th Annual International Conference of the Society for Chaos Theory in Psychology & Life Sciences, University of Texas, San Marcos, TX, July 22-24, 2010.