Search Results
Working Paper
Default correlation: an analytical result
Evaluating default correlations and the probabilities of multiple defaults is an important task in credit analysis and risk management, but it has never been an easy one because default correlations cannot be measured directly. This paper provides, for the first time, an analytical formula for calculating default correlations based on a first-passage-time model that can be easily implemented and conveniently used in a variety of financial applications. This paper also provides a theoretical justification for many empirical results found in the literature and increases our understanding of the ...
Working Paper
Path-dependent option valuation when the underlying path is discontinuous
The payoffs of path-dependent options depend not only on the final values, but also on the sample paths of the prices of the underlying assets. A rigorous modeling of the underlying asset price processes which can appropriately describe the sample paths is therefore critical for pricing path-dependent options. This paper allows for discontinuities in the sample paths of the underlying asset prices by assuming that these prices follow jump diffusion processes. A general yet tractable approach is presented to value a variety of path-dependent options with discontinuous processes. The numerical ...
Working Paper
Forecasting long- and short-horizon stock returns in a unified framework
If stock prices do not follow random walks, what processes do they follow? This question is important not only for forecasting purpose, but also for theoretical analyses and derivative pricing where a tractable model of the movement of underlying stock prices is needed. Although several models have been proposed to capture the predictability of stock returns, their empirical performances have not been evaluated. This paper evaluates some popular models using a Kalman Filter technique and finds that they have serious flaws. The paper then proposes an alternative parsimonious state-space model ...
Working Paper
Stock market fluctuations and the term structure
This paper uses the term structure of interest rates to explain the variations of stock prices and stock returns. It shows that interest rates have an important impact on stock returns, especially at long horizons. The hypothesis that expected stock returns move one-for-one with ex ante interest rates, which has been rejected strongly in other studies using short horizon data, is supported by long horizon data. The paper proposes, for the first time, a single measure---the present value of forward interest rates---to summarize the information of the term structure that is useful in ...
Working Paper
A jump-diffusion approach to modeling credit risk and valuing defaultable securities
The existing structural models of credit risk have relied almost exclusively on diffusion processes to model the evolution of firm value. While a diffusion approach is convenient, it has produced very disappointing results in empirical application. Jones, Mason, and Rosenfeld (1984) find that the credit spreads on corporate bonds are too high to be matched by the diffusion approach. Also, because the instantaneous default probability of a healthy firm is zero under a continuous process, the diffusion approach predicts that the term structure of credit spreads should always start at zero and ...
Working Paper
Credit derivatives in banking: useful tools for managing risk?
We model the effects on banks of the introduction of a market for credit derivatives--in particular, credit default swaps. A bank can use such swaps to temporarily transfer credit risks of their loans to others, reducing the likelihood that defaulting loans would trigger the bank's financial distress. Because credit derivatives are more flexible at transferring risks than are other, more established tools, such as loan sales without recourse, these instruments make it easier for banks to circumvent the ``lemons'' problem caused by banks' superior information about the credit quality of their ...