Jack Bao

Bond Illiquidity and Excess Volatility

This paper examines the connection between the return volatilities of corporate bonds, equities, and Treasuries under the Merton model with stochastic interest rates. Constructing empirical volatilities using bond returns over daily, weekly, and monthly horizons, we find that empirical bond volatilities are too high to be explained by equity and Treasury volatilities. Furthermore, the results are robust to using credit default swaps rather than corporate bonds to measure volatility in the credit market. At the daily return horizon, the excess volatility of corporate bonds is related to known liquidity proxies. However, this relation disappears at the monthly horizon even though corporate bonds continue to be excessively volatile. Thus, there appears to be a disconnect between corporate bonds and equities that goes beyond the illiquidity of corporate bonds.

Liquidity of Corporate Bonds

This paper examines the liquidity of corporate bonds and its asset-pricing implications using a novel measure of illiquidity based on the magnitude of transitory price movements. Using transaction-level data for a broad cross-section of corporate bonds from 2003 through 2007, we find the illiquidity in corporate bonds to be significant, substantially greater than what can be explained by bid-ask bounce, and closely linked to liquidity-related bond characteristics. More importantly, we find a strong commonality in the time variation of bond illiquidity, which rises sharply during market crises and reaches an all-time high during the recent sub-prime mortgage crisis. Monthly changes in this aggregate bond illiquidity are strongly related to changes in the CBOE VIX Index and lagged stock market returns. Examining its relation with bond pricing, we find that our measure of illiquidity explains the cross-sectional variation in average bond yield spreads with large economic significance.

The Volcker Rule and Market-Making in Times of Stress

Focusing on downgrades as stress events that drive the selling of corporate bonds, we document that the illiquidity of stressed bonds has increased after the Volcker Rule. Dealers regulated by the Rule have decreased their market-making activities while non-Volcker-affected dealers have stepped in to provide some additional liquidity. Furthermore, even Volcker-affected dealers that are not constrained by Basel III and CCAR regulations change their behavior, inconsistent with the effects being driven by these other regulations. Since Volcker-affected dealers have been the main liquidity providers, the net effect is that bonds are less liquid during times of stress due to the Volcker Rule.

Why Do Firms Issue Secured Debt

We empirically examine theories of secured debt. Credit risk and asset volatility increase with secured debt issuance, and the strength of this association is unrelated to contemporaneous investment. Hand-collected data reveals most secured debt is secured on all assets of the firm and rarely originates from collateralizing unsecured debt. A difference-in-differences analysis shows that shocks to the likelihood of debt overhang have no impact on the mix of secured and unsecured debt issued. Most secured debt is issued to bond against expropriating lenders rather than as described in theories related to debt overhang, facilitation of risk-shifting, and monitoring.

Systemic default and return predictability in the Stock and Bond Markets

Using a structural model of default, we construct a measure of systemic default defined as the probability that many firms default at the same time. Our estimation accounts for correlations in defaults between firms through common exposures to shocks. The systemic default measure spikes during recession periods and is strongly correlated with traditional credit-related macroeconomic measures such as the default spread and VIX. Furthermore, our measure predicts future equity and corporate bond index returns, particularly at the one-year horizon, and even after controlling for many traditional return predictors such as the dividend yield, default spread, inflation, and tail risk. These predictability results are robust to out-of-sample tests.

Prices and Volatilities in the Corporate Bond Market

We document a strong positive cross-sectional relation between corporate bond yield spreads and bond return volatilities. As corporate bond prices are generally attributable to both credit risk and illiquidity as discussed in Huang and Huang (2012), we apply a decomposition methodology to quantify the relative contributions of credit and illiquidity. Overall, our credit and illiquidity proxies can explain almost three quarters of the yield spread-bond volatility relation with credit and illiquidity contributing in a 70:30 ratio. Furthermore, we find that the credit portion of the yield spread-bond volatility relation is important even after controlling for equity volatility. The relation between yield spreads and volatilities is robust to different sample periods, including the financial crisis. We also find the ratio to be smaller for the investment-grade sub-sample, consistent with credit risk being relatively more important for understanding the yield spread-volatility relation in speculative-grade bonds.