NBER Publications by Zhiguo He

We develop a dynamic model of debt runs on a firm, which invests in an illiquid asset by rolling over staggered short-term debt contracts. We derive a unique threshold equilibrium, in which creditors coordinate their asynchronous rollover decisions based on the firm's publicly observable and time-varying fundamental. Fear of the firm's future rollover risk motivates each maturing creditor to run ahead of others even when the firm is still solvent. Our model provides implications on the roles played by volatility, illiquidity and debt maturity in driving debt runs, as well as on firms' capital adequacy standards and credit risk.

This paper studies optimal contracting in delegated asset management when a fund manager can exert unobservable effort and take unobservable investment positions in multiple markets. A key insight is that while giving the manager flexibility to invest in multiple markets increases investment efficiency, it weakens the link between fund performance and the manager's effort in his designated market, thus increasing agency cost. Building on this tradeoff, our model explains the existence of funds with narrow investment mandates, and provides a set of testable implications for a varying degree of investment flexibility across funds. These results shed light on capital immobility in financial markets, market segmentation, and the architecture of financial institutions.

We present a model to study the dynamics of risk premia during crises in asset markets where the marginal investor is a financial intermediary. Intermediaries face a constraint on raising equity capital. When the constraint binds, so that intermediaries' equity capital is scarce, risk premia rise to reflect the capital scarcity. We calibrate the model and show that it does well in matching two aspects of crises: the nonlinearity of risk premia during crisis episodes; and, the speed of adjustment in risk premia from a crisis back to pre-crisis levels. We use the model to quantitatively evaluate the effectiveness of a variety of central bank policies, including reducing intermediaries' borrowing costs, infusing equity capital, and directly intervening in distressed asset markets. All of ...

We develop a model in which the capital of the intermediary sector plays a critical role in determining asset prices. The model is cast within a dynamic general equilibrium economy, and the role for intermediation is derived endogenously based on optimal contracting considerations. Low intermediary capital reduces the risk-bearing capacity of the marginal investor. We show how this force helps to explain patterns during financial crises. The model replicates the observed rise during crises in Sharpe ratios, conditional volatility, correlation in price movements of assets held by the intermediary sector, and fall in riskless interest rates. In a dynamic context, we show that aversion to drops in intermediary capital can generate a two-factor asset pricing model with a role for both a market...