Illiquidity and All Its Friends
回顾了关于非流动性及其相关现象（市场冻结、抛售、传染、破产和救助）的已知和未知，分析了市场崩溃的原因，并从宏观视角探讨了流动性短缺、会计规则和资本充足率如何应对资产价格，强调宏观审慎政策的必要性。
The recent crisis was characterized by massive illiquidity. This paper reviews what we know and don't know about illiquidity and all its friends: market freezes, fire sales, contagion, and ultimately insolvencies and bailouts. It first explains why liquidity cannot easily be apprehended through a single statistic, and asks whether liquidity should be regulated given that a capital adequacy requirement is already in place. The paper then analyzes market breakdowns due to either adverse selection or shortages of financial muscle, and explains why such breakdowns are endogenous to balance sheet choices and to information acquisition. It then looks at what economics can contribute to the debate on systemic risk and its containment. Finally, the paper takes a macroeconomic perspective, discusses shortages of aggregate liquidity, and analyzes how market value accounting and capital adequacy should react to asset prices. It concludes with a topical form of liquidity provision, monetary bailouts and recapitalizations, and analyzes optimal combinations thereof; it stresses the need for macro-prudential policies.