Challenges to Estimating Contagion Effects from Observational Data

  • Elizabeth L. OgburnEmail author
Part of the Computational Social Sciences book series (CSS)


A growing body of literature attempts to learn about contagion using observational (i.e., non-experimental) data collected from a single social network. While the conclusions of these studies may be correct, the methods rely on assumptions that are likely—and sometimes guaranteed to be—false, and therefore the evidence for the conclusions is often weaker than it seems. Developing methods that do not need to rely on implausible assumptions is an incredibly challenging and important open problem in statistics. Appropriate methods don’t (yet!) exist, so researchers hoping to learn about contagion from observational social network data are sometimes faced with a dilemma: they can abandon their research program, or they can use inappropriate methods. This chapter will focus on the challenges and the open problems and will not weigh in on that dilemma, except to mention here that the most responsible way to use any statistical method, especially when it is well-known that the assumptions on which it rests do not hold, is with a healthy dose of skepticism, with honest acknowledgment and deep understanding of the limitations, and with copious caveats about how to interpret the results.



This work was funded by the Office of Naval Research grant N00014-15-1-2343.


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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Johns Hopkins Bloomberg School of Public HealthBaltimoreUSA

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