Comment on "Why and When 'Flawed' Social Network Analyses Still Yield Valid Tests of no Contagion".
VanderWeele et al.'s paper is a useful contribution to the on-going scientific conversation about the detection of contagion from purely observational data. It is especially helpful as a corrective to some of the more extreme statements of Lyons (2011). Unfortunately, this paper, too, goes too far in some places, and so needs some correction itself.
Carnegie Mellon University.
Cosma Rohilla
CR
Shalizi
causal inference; contagion; social influence; social networks