One of the major virtues of panel data models is the possibility to control for unobserved and unobservable heterogeneity at the unit (individual, firm, sector...) level, even when this is correlated with the variables included on the right hand side of the equation. By assuming an additive...

Negative values for estimated variances can arise in a panel data context. Empirical and theoretical literature dismisses the problem as not serious and a practical solution is to replace negative variances by its boundary value, i.e. zero. While this is not a concern when the individual...

This paper aims at characterizing the dynamics of R&D competition within the pharmaceutical domain, focusing on the role of patent disclosure, the extent of uncertainty, and role of scientific advances. Following the empirical literature in the economics of innovation, we employ patents as a...

During the last thirty years health care expenditure (HCE) has been growing much more rapidly than GDP in all OECD countries posing increasing concern on the long-term sustainability of current trends. Against this background, we look at the determinants of HCE in European countries, explicitly...

This paper aims at examining whether an increased stringency of Intellectual Property Right (IPR) protection is apt to stimulate international cooperation on research projects between developed and emerging countries. To address this issue, we look both at scientific and technological...

We propose a novel procedure, built within a Generalized Method of Moments framework, which exploits unpaired observations (singletons) to increase the efficiency of longitudinal fixed effect estimates. The approach allows increasing estimation efficiency, while properly tackling the bias due to...