A prominent threat to causal inference about peer effects in social science studies is the presence of homophily bias , that is, social influence between friends and families is entangled with common characteristics or underlying similarities that form close connections. Analysis of social study data has suggested that certain health conditions such as obesity and psychological states including happiness and loneliness can spread between friends and relatives. However, such analyses of peer effects or contagion effects have come under criticism because homophily bias may compromise the causal statement. We develop a regression-based approach which leverages a negative control exposure for identification and estimation of contagion effects on additive or multiplicative scales, in the presence of homophily bias. We apply our methods to evaluate the peer effect of obesity in Framingham Offspring Study.

中文翻译：

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二元同伴效应分析中基于回归的同质性负控制


社会科学研究中同伴效应因果推断的一个突出威胁是同质性偏见的存在，即朋友和家人之间的社会影响与形成密切联系的共同特征或潜在相似性纠缠在一起。社会研究数据分析表明，某些健康状况（例如肥胖）和心理状态（包括快乐和孤独）可以在朋友和亲戚之间传播。然而，这种对同伴效应或传染效应的分析受到了批评，因为同质性偏见可能会损害因果关系的陈述。我们开发了一种基于回归的方法，在存在同质偏差的情况下，利用阴性对照暴露来识别和估计加法或乘法尺度上的传染效应。我们在弗雷明汉后代研究中应用我们的方法来评估肥胖的同伴效应。