Exports, investment and policy uncertainty
研究了18个大型经济体的政策不确定性如何影响其出口，发现政策不确定性上升会降低贸易总值和出口企业数量，但可能提高现有出口企业的平均出口额，且在高沉没成本行业中影响更显著。
Abstract Building on a literature that underscores the value of delaying investment in the face of uncertainty, we study how policy uncertainty in 18 large economies affects exports to these economies. We decompose aggregate bilateral trade flows from 1995 to 2013 into intensive and extensive margin components and employ a gravity specification to assess the impact of policy uncertainty on each margin separately. Consistent with theory, increases in policy uncertainty decrease both trade values and the extensive margin but, if anything, increase the intensive margin. In further tests, we use various proxies for sunk export costs and demonstrate that the effects of policy uncertainty are more pronounced where sunk costs are higher.