Search Results
Working Paper
Volatility puzzles: a unified framework for gauging return-volatility regressions
This paper provides a simple unified framework for assessing the empirical linkages between returns and realized and implied volatilities. First, we show that whereas the volatility feedback effect as measured by the sign of the correlation between contemporaneous return and realized volatility depends importantly on the underlying structural model parameters, the correlation between return and implied volatility is unambiguously positive for all reasonable parameter configurations. Second, the lagged return-volatility asymmetry, or the leverage effect, is always stronger for implied than ...
Working Paper
Realized jumps on financial markets and predicting credit spreads
This paper extends the jump detection method based on bi-power variation to identify realized jumps on financial markets and to estimate parametrically the jump intensity, mean, and variance. Finite sample evidence suggests that jump parameters can be accurately estimated and that the statistical inferences can be reliable, assuming that jumps are rare and large. Applications to equity market, treasury bond, and exchange rate reveal important differences in jump frequencies and volatilities across asset classes over time. For investment grade bond spread indices, the estimated jump volatility ...
Working Paper
Ambiguity Aversion and Variance Premium
This paper offers an ambiguity-based interpretation of variance premium?the difference between risk-neutral and objective expectations of market return variance?as a compounding effect of both belief distortion and variance differential regarding the uncertain economic regimes. Our approach endogenously generates variance premium without imposing exogenous stochastic volatility or jumps in consumption process. Such a framework can reasonably match the mean variance premium as well as the mean equity premium, equity volatility, and the mean risk-free rate in the data. We find that about 96 ...
Working Paper
A study of the finite sample properties of EMM, GMM, QMLE, and MLE for a square-root interest rate diffusion model
This paper performs a Monte Carlo study on Efficient Method of Moments (EMM), Generalized Method of Moments (GMM), Quasi-Maximum Likelihood Estimation (QMLE), and Maximum Likelihood Estimation (MLE) for a continuous-time square-root model under two challenging scenarios--high persistence in mean and strong conditional volatility--that are commonly found in estimating the interest rate process. MLE turns out to be the most efficient of the four methods, but its finite sample inference and convergence rate suffer severely from approximating the likelihood function, especially in the scenario of ...
Working Paper
Variance risk premiums and the forward premium puzzle
This paper presents evidence that the foreign exchange appreciation is predictable by the currency variance risk premium at a medium 6-month horizon and by the stock variance risk premium at a short 1-month horizon. Although currency variance risk premiums are highly correlated with each other over longer horizons, their correlations with stock variance risk premiums are quite low. Interestingly the currency variance risk premium has no predictive power for stock returns. We rationalize these findings in a consumption-based asset pricing model with orthogonal local and global economic ...
Working Paper
Term structure of interest rates with regime shifts
We develop a term structure model where the short interest rate and the market price of risks are subject to discrete regime shifts. Empirical evidence from Efficient Method of Moments estimation provides considerable support for the regime shifts model. Standard models, which include affine specifications with up to three factors, are sharply rejected in the data. Our diagnostics show that only the regime shifts model can account for the well documented violations of the expectations hypothesis, the observed conditional volatility, and the conditional correlation across yields. We find that ...
Working Paper
Jump-diffusion term structure and Ito conditional moment generator
This paper implements a Multivariate Weighted Nonlinear Least Square estimator for a class of jump-diffusion interest rate processes (hereafter MWNLS-JD), which also admit closed-form solutions to bond prices under a no-arbitrage argument. The instantaneous interest rate is modeled as a mixture of a square-root diffusion process and a Poisson jump process. One can derive analytically the first four conditional moments, which form the basis of the MWNLS-JD estimator. A diagnostic conditional moment test can also be constructed from the fitted moment conditions. The market prices of diffusion ...
Working Paper
Specification analysis of structural credit risk models
In this paper we conduct a specification analysis of structural credit risk models, using term structure of credit default swap (CDS) spreads and equity volatility from high-frequency return data. Our study provides consistent econometric estimation of the pricing model parameters and specification tests based on the joint behavior of time-series asset dynamics and cross-sectional pricing errors. Our empirical tests reject strongly the standard Merton (1974) model, the Black and Cox (1976) barrier model, and the Longstaff and Schwartz (1995) model with stochastic interest rates. The double ...
Working Paper
Itô conditional moment generator and the estimation of short rate processes
This paper exploits the It's formula to derive the conditional moments vector for the class of interest rate models that allow for nonlinear volatility and flexible jump specifications. Such a characterization of continuous-time processes by the Ito Conditional Moment Generator noticeably enlarges the admissible set beyond the affine jump-diffusion class. A simple GMM estimator can be constructed based on the analytical solution to the lower order moments, with natural diagnostics of the conditional mean, variance, skewness, and kurtosis. Monte Carlo evidence suggests that the proposed ...
Working Paper
Dynamic estimation of volatility risk premia and investor risk aversion from option-implied and realized volatilities
This paper proposes a method for constructing a volatility risk premium, or investor risk aversion, index. The method is intuitive and simple to implement, relying on the sample moments of the recently popularized model-free realized and option-implied volatility measures. A small-scale Monte Carlo experiment suggests that the procedure works well in practice. Implementing the procedure with actual S&P 500 option-implied volatilities and high-frequency five-minute-based realized volatilities results in significant temporal dependencies in the estimated stochastic volatility risk premium, ...