Do we need social networks to model changes in human behaviour?

Richard Blythe (University of Edinburgh)

Social networks are a familiar concept both for network scientists and lay people: indeed, in describing concepts like the degree of a node, it is natural to use examples like “the number of friends you have”. Social networks are also the obvious substrate on which the dynamics of human behaviour play out. This applies particularly to aspects of ‘culture’, that is, the totality of all behaviour that is acquired by learning from others. In this talk, I will discuss simple models of social learning and focus particularly on the way that social network does - and perhaps more interestingly, in some cases - does not affect the dynamics of cultural change at the population scale. With specific reference to changes in language across multiple speech communities and extended periods of time, I will argue that the heterogeneity characteristic of social networks may offer an explanation of a surprising lack of sensitivity to the rate of change over space and time.