Are initial competitive advantages self-reinforcing, so that markets exhibit an endogenous tendency to be dominated by only a few firms? Although this question is of great economic importance, no systematic empirical study has yet addressed it. Therefore, we examine experimentally whether firms...

The bivariate probit model is frequently used for estimating the effect of an endogenous binary regressor on a binary outcome variable. This paper discusses simple modifications that maintain the probit assumption for the marginal distributions while introducing non-normal dependence among the...

This paper investigates if multinationals in.uence the political process through lobbying more effectively than national firms. First, I introduce a model which contrasts a multinational's incentives for lobbying with those of a national firm. Then the effect of lobbying on the political...

As previously argued, the correlation between included and omitted regressors generally causes inconsistency of standard estimators for count data models. Using a specific residual function and suitable instruments, a consistent generalized method of moments estimator can be obtained under...

We investigate how various institutional settings affect a network provider's incentives to invest in infrastructure quality. Under reasonable assumptions on demand, investment incentives turn out to be smaller under vertical separation than under vertical integration, though we also provide...

This article investigates power and size of some tests for exogeneity of a binary explanatory variable in count models by conducting extensive Monte Carlo simulations. The tests under consideration are Hausman contrast tests as well as univariate Wald tests, including a new test of notably easy...

This paper surveys recent approaches towards lobbying if interest groups influence the decision of an incumbent government. It describes the two main channels of influence which mainly exist in parallel, namely contribution payments and the transmission of information through lobbying. Recent...

This paper studies the Cass-Koopmans-Ramsey model of optimal economic growth in the presence of loss aversion and habit formation. The representative agent's preferences for consumption can be gradually varied between the standard constant intertemporal elasticity of substitution (CIES) case and...