The aim of the paper is to relax distributional assumptions on the error terms, often imposed in parametric sample selection models to estimate causal effects, when plausible exclusion restrictions are not available. Within the principal stratification framework, we approximate the true...

The authors describe a new statistical concept called relevance from a conceptual and mathematical perspective, and based on their mathematical framework, they present a unified theory of relevance, regressions, and event studies. They also include numerical examples of how relevance is used to...

Recreational services are demanded because they generate benefits. The recreational benefits connected with a destination can be valued based on visitor preferences, which can aid in the formulation of an appropriate Natural Resource Management policy. Environmental and natural resource...

The aim of the paper is to relax distributional assumptions on the error terms, often imposed in parametric sample selection models to estimate causal effects, when plausible exclusion restrictions are not available. Within the principal stratification framework, we approximate the true...

The creation of the EU's Emission Trading Scheme (EU ETS) has turned the right to emit CO2 into a positively priced intermediate good for the affected firms. Firms thus face the decision whether to source compliance with the EU ETS within their boundaries or to acquire it through the permit...

In this paper we establish a full information maximum likelihood approach to estimating the sample selection model with endogenous covariates. We also provide a test for exogeneity which indicates whether endogeneity is in fact a matter or not. In contrast to other methods proposed in the...

Recent studies have documented extensive heterogeneity in firm performance within countries, and innovation has been found as an important determinant. This paper addresses the issue of innovation firm performance across countries. A growing number of national firm level studies on the...

Multivariate Tobit models are estimated using German cross?sectional data to test whether strategic complementarities exist between expenditures in four different types of ICT?components. If two ICT?components are complements, they are correlated (provided that agents act rationally)....

In the 1990s, patenting schemes changed in many respects: upcoming new technologies accelerated the shift from price competition towards competition based on technical inventions, a worldwide surge in patenting took place, and the ?patent thicket? arose as a consequence of strategic patenting....

This paper derives a three stage Cournot?oligopoly game for product innovation, expenditure on introducing the product and competition on the product market. Product innovation is assumed to increase consumer utility but is effective only if the innovating firm invests in marketing, so that...