Social Networks and Brexit: Evidence from a Trade Shock
研究发现，英国地区对华进口竞争暴露不仅直接影响脱欧支持率，还通过社交网络在相邻地区间产生溢出效应，信息流动是可能的传导渠道。
Regional exposure to Chinese import competition has often been linked to support for the Leave option in the 2016 UK EU membership referendum. Looking at 143 harmonised International Territorial Level 3 (ITL3) regions covering England and Wales, and using data on the density of online social ties between them, I show that regional support for leaving the EU was also associated with exposure in socially connected regions. I first delineate 18 commuting zones based on interregional flows over three Census years. For each region, I then construct a measure of own exposure to Chinese import competition and a measure of exposure in a set of social neighbours located outside its commuting zone. Exploiting variation within commuting zones, and using an instrumental variable approach, I find that the two measures have comparable positive effects on the regional share of the Leave vote. In a series of checks, I do not find evidence that the effect of social neighbours’ exposure is driven by an economic channel or a relationship between import competition and social ties. I also corroborate the regional results using survey data on vote choice. I interpret these findings as indicative of social spillovers between local labour markets: information flows from social neighbours are a likely channel behind the estimated spillover effects on voting outcomes.