Bond Premium Cyclicality and Liquidity Traps
研究发现安全资产短缺会导致流动性陷阱，债券溢价的周期性（反周期或顺周期）决定了政府债务在陷阱中的扩张效应，并基于大衰退数据校准模型表明提高债务GDP比可防止自我实现的陷阱。
Abstract Safe asset shortages can expose an economy to liquidity traps. The nature of these traps is determined by the cyclicality of the bond premium. A counter-cyclical bond premium opens the possibility of expectations-driven liquidity traps in which small issuances of government debt crowd out private debt and reduce output. In contrast, when the bond premium is pro-cyclical and the economy is in a liquidity trap, government debt is expansionary. In the data, we find evidence of a counter-cyclical bond premium. Large interventions can prevent the emergence of self-fulfilling traps, but they require sufficient fiscal capacity. In a quantitative model calibrated to the Great Recession, a promise to increase the government debt-to-GDP ratio by 20 percentage points precludes the possibility of self-fulfilling traps.