COVID-19 anti-contagion policies and economic support measures in the USA
研究美国各州疫情防控措施强度对感染增长率的影响，发现经济支持措施通过减少工作时间增强防控效果，但仅在中等强度政策下最有效。
Abstract Current literature assumes that non-pharmaceutical interventions (NPIs) reduce COVID-19 infections uniformly, that is, irrespectively of their strength. The role of economic support measures (ESM) in controlling the virus is also overlooked. Using a panel threshold model of COVID-19 cases in the US states, we identify three distinct regimes of ‘low’, ‘medium’, and ‘high’ severity interventions; the latter being more effective towards reducing infections growth. ESM increase the efficacy of NPIs through a behavioural channel that lowers the workplace hours supplied by individuals. Nonetheless, when containment policies are not very stringent (‘low’ regime) or are too draconian (‘high’ regime), ESM are less effective towards suppressing the pandemic. Finally, we find that the largest impact towards reducing the growth of infections comes jointly from school closures, workplace closures, cancelation of public events, and restrictions on internal movement, followed by the stay-at-home requirements, and the closure of public transport.