Most discrete time literature uses the beta that results from a regression of an asset's simple returns on various factors to quantify risk. The departing point for this thesis is the consistent use of log-returns. When log-returns are considered, the relevant measure of systematic risk becomes...

With the emergence and expansion of credit derivatives, which are financial instruments that are based on corporate bonds and provide their holders a protection against default, the importance of estimating probabilities of default has reached an unprecedented level. We have developed a Bayesian...

The term structure of interest rates is used to price defaultable bonds and credit derivatives, as well as to infer the quality of bonds for risk management purposes. We introduce a new framework for estimating the term structure of interest rates for corporate bonds. The proposed model jointly...

We present a series of models capturing the non-stationarities and dependencies in the variance of yields on natural gas futures. Both univariate and multivariate models are explored, based on the ARIMA and Hidden-Markov methodologies. The models capture the effects uncovered through various...

The White information matrix (IM) test is applied to the linear regression model with autoregressive conditional heteroskedastic (ARCH) errors. ARCH models are used widely in analyzing economic and financial time series data. However, in practice, the models are not often thoroughly tested. We...

In this paper, we introduce DSPMD, discretely sampled process with pre-specified marginals and pre-specified dependence, and SRLMD, series representation for Levy process with pre-specified marginals and pre-specified dependence. In the DSPMD for Levy processes, some regular copula can be...