We analyze a sequence of single-server queueing systems with impatient customers in heavy traffic. Our state process is the offered waiting time, and the customer arrival process has a state dependent intensity. Service times and customer patient-times are independent; i.i.d. with general...

We study long time asymptotic properties of constrained diffusions that arise in the heavy traffic analysis of multiclass queueing networks. We first consider the classical diffusion model with constant coefficients, namely a semimartingale reflecting Brownian motion (SRBM) in a d-dimensional...

We first consider a multi-dimensional reflected fractional Brownian motion process on the positive orthant with the Hurst parameter H∈(0,1). In particular, when H1/2, this model serves to approximate fluid stochastic network models fed by a big number of heavy tailed ON/OFF sources in heavy...

We consider the problem of estimating parameters of stochastic differential equations (SDEs) with discrete-time observations that are either completely or partially observed. The transition density between two observations is generally unknown. We propose an importance sampling approach with an...

We examined the time series properties of the foreign exchange market for 1990–2008 in relation to the history of the currency crises using the minimum spanning tree (MST) approach and made several meaningful observations about the MST of currencies. First, around currency crises, the mean...

We study structural models of stochastic discount factors and explore alternative methods of estimating such models using data on macroeconomic risk and asset returns. Particular attention is devoted to recursive utility models in which risk aversion can be modified without altering...

We examine whether the relationship between market volatility and network properties in the low-frequency level can be applied to the high-frequency level. For the analysis, we use the minimum spanning tree (MST) method constructed from intraday Korean stock market data. The results show that...

This paper develops a general equilibrium model to study the impact of aggregate fluctuations in idiosyncratic volatility that incorporates the endogenous determination of investment opportunities. By making investment options more valuable, an increase in volatility encourages the creation of...