In this paper, we present, and test, a novel mathematical formulation of how information spreads online. Our model is based on fuzzy trace theory (FTT)—a leading account of decision under risk—which emphasizes the combined roles of mental representation, message content, social values, and individual differences. FTT posits that individuals encode multiple representations of a stimulus, such as online information, in parallel. These representations are referred to as gist—the essential meaning of the information—and verbatim—a detailed symbolic representation of the stimulus. Thus, our model incorporates factors capturing the extent to which the individual “gets the gist” (i.e., is able to extract meaningful information) and is therefore illuminated by the content of the message. We also incorporate a factor capturing motivation to share, such as may be triggered by material containing especially compelling media (e.g., vivid photos or surprising content). Our formulation is novel because it combines these cognitive and motivational considerations into a common computational framework.
August 12, 2019