Social Connections and COVID19 Vaccination
研究了美国县级社会网络对COVID-19疫苗接种的影响，区分了即时和长期网络效应，发现即时友谊网络效应为正，长期效应不显著。
This paper unpacks the effects of social networks on county-level COVID19 vaccinations in the US. We jointly assess the contemporaneous and dynamic network ef-fects of vaccination exposure, to distinguish between network-mediated contemporane-ous effects (e.g., "vaccine-hunter" Facebook groups crowd-source information about ac-cess and efficacy) and longer-term effects (e.g., vaccine exposure chips away vaccine hesi-tancy). Accounting for possible correlated shocks, socio-economic/spatial confounders, and pandemic-related shifters, we find positive stage-of-pandemic dependent contempo-raneous friendship network effects, and null dynamic network effect, thus sharply dis-tinguishing COVID19 vaccination from other infection-mitigating practices in terms of openness to social-learning over time.