The Influence “Paradox”: When More Network Ties Lead to Less Change
研究发现，当社会联系集中在少数人身上时，针对这些人的干预反而难以推动广泛的行为扩散，尤其对需要高社会强化的行为，基于洪都拉斯随机实验和模拟验证了这一网络结构悖论。
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.