This paper develops and implements a GMM estimator for latent class models suitable for count data. The estimator uses conditional moment restrictions derived from standard count models. Both the efficient and consistent variants are considered. The implementation of optimal GMM based on...

This paper reconsiders the equity issue in Swedish health care utilisation previously analyzed by Gerdtham (Health Economics 6, 303-319, 1997) within the framework of the standard two-part model. Departing from the user/nonuser distinction, we use the more flexible framework of the finite...

This paper investigates the nature and consequences of sample attrition in a unique longitudinal survey of medical doctors. We describe the patterns of non-response and examine if attrition affects the econometric analysis of medical labour market outcomes using the estimation of physician...

Blonigen has studied the Japanese foreign direct investment (FDI) in the United States using panel count models and data for 1975-92. He reports the overall finding that appreciation of Japanese yen had a positive impact on Japanese FDI in the U.S.A. This paper reexamines the robustness of this...

This article explores alternative approaches to modeling the relationship between the number of patents and research and development expenditure. Patent counts typically exhibit long upper tails that are inadequately modeled by standard Poisson and negative binomial regression models. We compare...