Really Uncertain Business Cycles
研究了不确定性在商业周期中的作用，发现微观经济不确定性在经济衰退时急剧上升，不确定性冲击可使GDP下降约2.5%，但需结合一阶矩冲击才能拟合消费数据，且不确定性会削弱工资补贴等一阶矩政策的短期效果。
We investigate the role of uncertainty in business cycles. First, we demonstrate that microeconomic uncertainty rises sharply during recessions, including during the Great Recession of 2007–2009. Second, we show that uncertainty shocks can generate drops in gross domestic product of around 2.5% in a dynamic stochastic general equilibrium model with heterogeneous firms. However, we also find that uncertainty shocks need to be supplemented by first†moment shocks to fit consumption over the cycle. So our data and simulations suggest recessions are best modelled as being driven by shocks with a negative first moment and a positive second moment. Finally, we show that increased uncertainty can make first†moment policies, like wage subsidies, temporarily less effective because firms become more cautious in responding to price changes.