Abstract

The influence of friends in shaping students’ educational expectations has received considerable theoretical and empirical attention in past research. However, few studies have directly tackled the methodological problems associated with estimating such influence effects. In particular, the separation of selection effects—with students selecting friends with similar educational expectations—from influence effects has remained elusive. In this study, we therefore investigate whether friend influence persists once we account for selection effects and other confounding network-related processes. In addition, we quantify the contribution of selection and influence to the similarity of educational expectations among friends. We rely on two-wave longitudinal data on 1,821 German secondary school students in 77 classrooms and multilevel random-coefficients stochastic actor-oriented models for the coevolution of networks and behaviour. Our results demonstrate that both selection and influence contribute to expectation-based similarity and that selection effects are substantial. This shows that without explicitly accounting for selection, estimates of friend influence effects are likely to be biased.

中文翻译：

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为什么朋友会有类似的教育期望？分离影响和选择效果

摘要

在过去的研究中，朋友对塑造学生的教育期望的影响受到了相当大的理论和经验关注。但是，很少有研究直接解决与估计这种影响有关的方法论问题。特别是，选择效应（学生选择具有相似教育期望的朋友）与影响效应之间的分离仍然难以捉摸。因此，在这项研究中，一旦我们考虑了选择效应和其他与网络相关的混杂过程，我们就会调查朋友的影响力是否持续存在。另外，我们量化选择和影响对朋友之间教育期望相似性的贡献。我们依赖于1的两波纵向数据 821名德国中学生在77个教室中学习，并且采用多层随机系数随机行为者导向模型来实现网络与行为的协同进化。我们的结果表明，选择和影响都有助于基于期望的相似性，并且选择效果是巨大的。这表明，在没有明确考虑选择的情况下，对朋友影响力的估计可能会产生偏差。