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In this chapter, we assess whether the roller-coaster pattern of homicides in New York City beginning in 1985 fits a contagion model and identify mechanisms of social contagion that predict its spread across social and physical space. This framework for interpreting the homicide trends as an epidemic includes two perspectives. First, the sharp rise and fall are indicative of a nonlinear pattern in which the phenomenon spreads at a rate far beyond what would be predicted by exposure to some external factor and declines in a similar pattern in which the reduction from year to year exceeds what might be expected by linear regression trends. This leads to the second perspective: the factors leading to its spread are not exogenous factors, as in the case of contamination or disaster. Instead, the nonlinear increase and decline suggest that the phenomenon is endemic to the people and places where its occurrence is highest and that this behavior may be effectively passed from one person to another through some process of contact or interaction.


Criminal Law | Juvenile Law | Law


This material has been published in "Social Contagion of Violence", edited by Daniel J. Flannery, Alexander T. Vazsonyi, and Irwin D. Waldman. This version is free to view and download for private research and study only. Not for re-distribution or re-use.