The social contagion hypothesis: comment on 'Social contagion theory: examining dynamic social networks and human behavior'

I reflect on the statistical methods of the ChristakisFowler studies on network-based contagion of traits by checking the sensitivity of these kinds of results to various alternate specifications and generative mechanisms. Despite the honest efforts of all involved, I remain pessimistic about establishing whether binary health outcomes or product adoptions are contagious if the evidence comes from simultaneously observed data. Copyright (C) 2012 John Wiley & Sons, Ltd.