Focal Points, Endogenous Processes, and Exogenous Shocks in the Autism Epidemic

Liu, Kayuet; Bearman, Peter Shawn

Autism prevalence has increased rapidly in the United States during the past two decades. We have previously shown that the diffusion of information about autism through spatially proximate social relations has contributed significantly to the epidemic. This study expands on this finding by identifying the focal points for interaction that drive the proximity effect on subsequent diagnoses. We then consider how diffusion dynamics through interaction at critical focal points, in tandem with exogenous shocks, could have shaped the spatial dynamics of autism in California. We achieve these goals through an empirically calibrated simulation model of the whole population of 3- to 9-year-olds in California. We show that in the absence of interaction at these foci—principally malls and schools—we would not observe an autism epidemic. We also explore the idea that epigenetic changes affecting one generation in the distal past could shape the precise spatial patterns we observe among the next generation.

Geographic Areas


  • thumnail for Bearman_2012_442272305.pdf Bearman_2012_442272305.pdf application/pdf 265 KB Download File

Also Published In

Sociological Methods and Research

More About This Work

Academic Units
Interdisciplinary Center for Innovative Theory and Empirics
Published Here
April 23, 2019


Keywords: autism, simulation, social interactions, environmental risks, diffusion