Agglomeration and Social Networks Lendület Research Group, Centre for Economic-and Regional Studies, Budapest, Hungary.
Spatial Dynamics Lab, University College Dublin, Dublin, Ireland.
Nat Commun. 2021 Feb 18;12(1):1143. doi: 10.1038/s41467-021-21465-0.
Social networks amplify inequalities by fundamental mechanisms of social tie formation such as homophily and triadic closure. These forces sharpen social segregation, which is reflected in fragmented social network structure. Geographical impediments such as distance and physical or administrative boundaries also reinforce social segregation. Yet, less is known about the joint relationships between social network structure, urban geography, and inequality. In this paper we analyze an online social network and find that the fragmentation of social networks is significantly higher in towns in which residential neighborhoods are divided by physical barriers such as rivers and railroads. Towns in which neighborhoods are relatively distant from the center of town and amenities are spatially concentrated are also more socially segregated. Using a two-stage model, we show that these urban geography features have significant relationships with income inequality via social network fragmentation. In other words, the geographic features of a place can compound economic inequalities via social networks.
社交网络通过社会联系形成的基本机制（如同质性和三元闭包）放大了不平等现象。这些力量加剧了社会隔离，这反映在碎片化的社交网络结构中。地理障碍，如距离和物理或行政边界，也加剧了社会隔离。然而，关于社交网络结构、城市地理和不平等之间的联合关系知之甚少。在本文中，我们分析了一个在线社交网络，发现居住社区被河流和铁路等物理障碍隔开的城镇中，社交网络的碎片化程度明显更高。邻里之间距离市中心较远，设施集中在空间上的城镇也更加社会隔离。通过两阶段模型，我们表明这些城市地理特征通过社交网络碎片化与收入不平等存在显著关系。换句话说，一个地方的地理特征可以通过社交网络使经济不平等加剧。
