The Information Content of Option-Implied Volatility for Credit Default Swap Valuation Charles Cao Fan Yu Zhaodong Zhong1 First Draft: November 12, 2005 Current Version: March 10, 2006 1Cao and Zhong are from the Smeal College of Business at the Pennsylvania State University, Email:
[email protected],
[email protected]. Yu is from the Paul Merage School of Business at the University of California, Irvine, Email:
[email protected]. We thank Philippe Jorion, Tom McNerney, Stuart Turnbull and seminar participants at the Pennsylvania State University for helpful comments. The Information Content of Option-Implied Volatility for Credit Default Swap Valuation Abstract This paper empirically examines the information content of option-implied volatility and historical volatility in determining the credit default swap (CDS) spread. Using Þrm-level time-series regressions, we Þnd that option-implied volatility dominates historical volatility in explaining CDS spreads. More importantly, the advantage of implied volatility is con- centrated among Þrms with lower credit ratings, higher option volume and open interest, and ÞrmsthathaveexperiencedimportantcrediteventssuchasasigniÞcant increase in the level of CDS spreads. To accommodate the inherently nonlinear relation between CDS spread and volatility, we estimate a structural credit risk model called “CreditGrades.” Assessing the performance of the model both in- and out-of-sample with either implied or historical volatility as input, we reach broadly similar conclusions. Our Þndings highlight the importance of choosing the right measure of volatility in understanding the dynamics of CDS spreads. 1Introduction Credit default swaps (CDS) are a class of credit derivatives that provide a payoff equal to the loss-given-default on bonds or loans of a reference entity, triggered by credit events such as default, bankruptcy, failure to pay, or restructuring.