Dipartimento di Scienze Economiche, Università Ca' Foscari di Venezia, and School for Advanced Studies in Venice, 30123 Venice, Italy.
Proc Natl Acad Sci U S A. 2010 Mar 16;107(11):4857-61. doi: 10.1073/pnas.0911793107. Epub 2010 Mar 8.
Homophily, the tendency of people to associate with others similar to themselves, is observed in many social networks, ranging from friendships to marriages to business relationships, and is based on a variety of characteristics, including race, age, gender, religion, and education. We present a technique for distinguishing two primary sources of homophily: biases in the preferences of individuals over the types of their friends and biases in the chances that people meet individuals of other types. We use this technique to analyze racial patterns in friendship networks in a set of American high schools from the Add Health dataset. Biases in preferences and biases in meeting rates are both highly significant in these data, and both types of biases differ significantly across races. Asians and Blacks are biased toward interacting with their own race at rates >7 times higher than Whites, whereas Hispanics exhibit an intermediate bias in meeting opportunities. Asians exhibit the least preference bias, valuing friendships with other types 90% as much as friendships with Asians, whereas Blacks and Hispanics value friendships with other types 55% and 65% as much as same-type friendships, respectively, and Whites fall in between, valuing other-type friendships 75% as much as friendships with Whites. Meetings are significantly more biased in large schools (>1,000 students) than in small schools (<1,000 students), and biases in preferences exhibit some significant variation with the median household income levels in the counties surrounding the schools.
同质性，即人们倾向于与和自己相似的人交往，这种现象在许多社交网络中都存在，包括友谊、婚姻和商业关系等，其基础是各种特征，包括种族、年龄、性别、宗教和教育程度。我们提出了一种区分同质性两种主要来源的技术：个体对朋友类型偏好的偏差，以及人们与其他类型的个体相遇机会的偏差。我们使用这种技术来分析来自 Add Health 数据集的一组美国高中的友谊网络中的种族模式。在这些数据中，偏好偏差和相遇率偏差都非常显著，而且这两种偏差在不同种族之间存在显著差异。亚洲人和黑人与自己种族互动的倾向性比白人高 7 倍以上，而西班牙裔则表现出中间的相遇机会偏差。亚洲人表现出的偏好偏差最小，将与其他类型的人的友谊价值视为与亚洲人的友谊价值的 90%，而黑人则分别将与其他类型的人的友谊价值视为与同类型的友谊价值的 55%和 65%，白人则处于两者之间，将与其他类型的人的友谊价值视为与白人的友谊价值的 75%。在拥有 1000 名以上学生的大型学校中，相遇机会的偏差比在拥有 1000 名以下学生的小型学校中更为明显，而且偏好偏差与学校周边县的家庭收入中位数水平有一定的显著差异。
