John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts.
Department of Sociology, Yale University, New Haven, Connecticut3Yale Institute for Network Science, Yale University, New Haven, Connecticut.
JAMA Intern Med. 2017 Mar 1;177(3):326-333. doi: 10.1001/jamainternmed.2016.8245.
Every day in the United States, more than 200 people are murdered or assaulted with a firearm. Little research has considered the role of interpersonal ties in the pathways through which gun violence spreads.
To evaluate the extent to which the people who will become subjects of gun violence can be predicted by modeling gun violence as an epidemic that is transmitted between individuals through social interactions.
DESIGN, SETTING, AND PARTICIPANTS: This study was an epidemiological analysis of a social network of individuals who were arrested during an 8-year period in Chicago, Illinois, with connections between people who were arrested together for the same offense. Modeling of the spread of gunshot violence over the network was assessed using a probabilistic contagion model that assumed individuals were subject to risks associated with being arrested together, in addition to demographic factors, such as age, sex, and neighborhood residence. Participants represented a network of 138 163 individuals who were arrested between January 1, 2006, and March 31, 2014 (29.9% of all individuals arrested in Chicago during this period), 9773 of whom were subjects of gun violence. Individuals were on average 27 years old at the midpoint of the study, predominantly male (82.0%) and black (75.6%), and often members of a gang (26.2%).
Explanation and prediction of becoming a subject of gun violence (fatal or nonfatal) using epidemic models based on person-to-person transmission through a social network.
Social contagion accounted for 63.1% of the 11 123 gunshot violence episodes; subjects of gun violence were shot on average 125 days after their infector (the person most responsible for exposing the subject to gunshot violence). Some subjects of gun violence were shot more than once. Models based on both social contagion and demographics performed best; when determining the 1.0% of people (n = 1382) considered at highest risk to be shot each day, the combined model identified 728 subjects of gun violence (6.5%) compared with 475 subjects of gun violence (4.3%) for the demographics model (53.3% increase) and 589 subjects of gun violence (5.3%) for the social contagion model (23.6% increase).
Gunshot violence follows an epidemic-like process of social contagion that is transmitted through networks of people by social interactions. Violence prevention efforts that account for social contagion, in addition to demographics, have the potential to prevent more shootings than efforts that focus on only demographics.
在美国，每天有超过 200 人被谋杀或被枪支袭击。很少有研究考虑人际关系在枪支暴力传播途径中的作用。
通过将枪支暴力建模为通过社交互动在个体之间传播的传染病，评估成为枪支暴力受害者的可能性。
设计、地点和参与者： 这是一项在伊利诺伊州芝加哥进行的 8 年期间被捕的个体社会网络的流行病学分析，其中被捕的人因同一罪行而被联系在一起。通过假设个体除了年龄、性别和居住社区等人口因素外，还受到因共同被捕而产生的风险的影响，使用概率传染模型来评估枪击暴力在网络中的传播。参与者代表了一个由 138163 名个体组成的网络，这些个体于 2006 年 1 月 1 日至 2014 年 3 月 31 日期间在芝加哥被捕（这期间被捕的所有个体的 29.9%），其中 9773 名是枪支暴力的受害者。在研究的中点，个体的平均年龄为 27 岁，主要是男性（82.0%）和黑人（75.6%），并且经常是帮派成员（26.2%）。
使用基于人际传播的传染病模型解释和预测成为枪支暴力（致命或非致命）的可能性，该模型基于社交网络。
社会传染解释了 11123 个枪击暴力事件中的 63.1%；枪支暴力的受害者在其感染者（最有可能使受害者暴露于枪击暴力的人）之后平均被枪击 125 天。一些枪支暴力的受害者被多次枪击。基于社会传染和人口统计学的模型表现最佳；当确定每天被认为处于最高风险的 1.0%（n=1382）的人时，综合模型确定了 728 名枪支暴力受害者（6.5%），而人口统计学模型确定了 475 名枪支暴力受害者（4.3%）（增加 53.3%），社会传染模型确定了 589 名枪支暴力受害者（5.3%）（增加 23.6%）。
枪击暴力遵循一种类似传染病的社会传染过程，通过社交互动在人与人之间的网络中传播。除了人口统计学因素外，考虑社会传染的暴力预防工作有可能比仅关注人口统计学因素的工作预防更多枪击事件。
