American Sociological Review · 2026 · Yuan Hsiao、Nicholas A. Christakis
中文摘要
行为与观念的扩散是许多领域的核心关切，与集体行动和创新采纳高度相关。一个常见假设是，社会网络中联系广泛的个体尤其具有影响力，因而是发起行为干预的良好目标。在此，我们主张，基于网络的靶向干预的有效性取决于社会联结在网络中的组织方式。我们提出存在一种结构性的“网络悖论”：当社会联结集中于少数联系广泛的个体周围时，聚焦于靶向这些个体在产生广泛扩散方面变得不那么有效。我们进一步主张，这一悖论对于需要高水平社会强化才能传播的行为尤为明显。我们开展了一项包含三部分的研究，包括理论分析、基于洪都拉斯健康实践随机实地试验的实证分析以及模拟。在三项研究中，结果都凸显了网络结构在以优先选择拥有更多联结的个体为特征的靶向方案下对塑造扩散动态的关键作用。当这些个体聚集在一起时，此类方案可能失效。我们的发现对于理解领导力与影响、创新、公共卫生与发展经济学干预以及营销具有启示意义。
Abstract
The diffusion of behaviors and ideas is a core concern in many fields and highly relevant to collective action and innovation adoption. A common assumption is that well-connected individuals within social networks are especially influential and so are good targets to initiate behavioral interventions. Here, we argue that the effectiveness of network-based targeting depends on how social ties are organized within a network. We theorize that there is a structural “network paradox”: when social ties are concentrated around a small number of well-connected individuals, a focus on targeting those individuals becomes less effective at generating broad diffusion. We further argue that this paradox is especially pronounced for behaviors that require high levels of social reinforcement to spread. We conducted a three-part study including theoretical analysis, empirical analysis based on a randomized field trial of health practices in Honduras, and simulations. Across all three studies, the results highlight the critical role of network structure in shaping diffusion dynamics under targeting protocols that privilege individuals with more ties. Such protocols may fail when those individuals are clustered together. Our findings have implications for understanding leadership and influence, innovation, public health and developmental economic interventions, and marketing.