The transition density of a diffusion process does not admit an explicit expression in general, which prevents the full maximum likelihood estimation (MLE) based on discretely observed sample paths. Aït-Sahalia [J. Finance 54 (1999) 1361–1395; Econometrica 70 (2002) 223–262] proposed asymptotic...

This paper considers the problem of parameter estimation in a general class of semiparametric models when observations are subject to missingness at random. The semiparametric models allow for estimating functions that are non-smooth with respect to the parameter. We propose a nonparametric...

The conventional Wilcoxon/Mann-Whitney test can be invalid for comparing treatment effects in the presence of missing values or in observational studies. This is because the missingness of the outcomes or the participation in the treatments may depend on certain pre-treatment variables. We...

Markov processes are used in a wide range of disciplines, including finance. The transition densities of these processes are often unknown. However, the conditional characteristic functions are more likely to be available, especially for Lévy-driven processes. We propose an empirical likelihood...

We propose two tests for the equality of covariance matrices between two high-dimensional populations. One test is on the whole variance-covariance matrices, and the other is on offdiagonal sub-matrices which define the covariance between two non-overlapping segments of the high-dimensional...

Motivated by the latest effort to employ banded matrices to estimate a high-dimensional covariance Σ , we propose a test for Σ being banded with possible diverging bandwidth. The test is adaptive to the “large p , small n ” situations without assuming a specific parametric distribution for...

The present study explores the relationship between coal consumption, industrial production and CO2 emissions in case of China and India for the period of 1971-2011. The structural break unit root test and cointegrating approach have been applied. The direction of causal relationship between the...

Several studies considered oil price as exchange rate determinants. The novelty of our paper is to test if the lagged oil price are statistically significant predictors of Moroccan and Tunisian exchange rate. We consider a stricter GARCH specifications (linear versus nonlinear, symmetric versus...

This paper investigates a simple risk management problem where an investor is forced to hold a risky asset and then allowed to trade put options on the asset. I simulate the distribution of returns for different quantities of options and investigate statistics from the distribution. In the first...

This is the second report produced under the project "Manpower Survey and Establishment of Labour Market Information System" NAM/90/020. The Establishment Survey, the subject matter of this report, was conducted during October 1992 to July 1993. Being a pioneering attempt in the Namibian...