In this paper, we propose a new approach to estimating sample selection models that combines Generalized Tukey Lambda (GTL) distributions with copulas. The GTL distribution is a versatile univariate distribution that permits a wide range of skewness and thick- or thin-tailed behavior in the data...

If the disturbances of a linear regression model are skewed and/or thick-tailed, a maximum likelihood estimator is efficient relative to the customary Ordinary Least Squares (OLS) estimator. In this paper, we specify a highly flexible Generalized Tukey Lambda (GTL) distribution to model skewed...

This paper examines the impact of a type of employment contract on starting wage and short-term wage growth. I estimate the differences in starting wage and wage growth patterns between temporary and permanent workers by using a dataset from the Netherlands. The data contain new graduates from...

I describe the commands heckmancopula and switchcopula, which implement copula-based maximum-likelihood estimations of sample-selection models. Copyright 2013 by StataCorp LP.

We derive the asymptotic variance of the Blinder-Oaxaca decomposition effects. We show that the delta method approach that builds on the assumption of fixed regressors understates true variability of the decomposition effects when regressors are stochastic. Our proposed variance estimator takes...

This paper compares the power of alternative tests for the level moment conditions in GMM estimation of a linear dynamic panel data model. The test statistic calculated conventionally can take on a negative value in finite samples even though it cannot be asymptotically. A straightforward...