We explore the determinants of usage of six different types of health care services, using the Medical Expenditure Panel Survey (MEPS) data, years 1996-2000. We apply a number of models for univariate count data, including semiparametric, semi-nonparametric and finite mixture models. We find...

Widely-used estimators such as the generalized method of moments (GMM) and quasi-maximum likelihood (QML) are not efficient in general. This study shows how the Hausman specification test may easily be corrected to be used with inefficient estimators. It introduces a related test that has better...