We propose a class of estimators of a received treatment effect on a dichotomous outcome among the treated subjects within covariate and treatment arm strata in randomized trials with non-compliance. Recent articles by Vansteelandt and Goethebeur (2003), and Robins and Rotnitzky (2004) have...

The present article proposes general single-step multiple testing procedures for controlling Type I error rates defined as arbitrary parameters of the distribution of the number of Type I errors, such as the generalized family-wise error rate. A key feature of our approach is the test statistics...

Marginal structural models (MSM) provide a powerful tool for estimating the causal effect of a treatment. These models, introduced by Robins (e.g. Robins (2000a), Robins (2000b), van der Laan and Robins (2002)), model the marginal distributions of treatment-specific counterfactual outcomes,...

An increasingly popular tool for nonparametric smoothing are penalized splines (P-splines) which use low-rank spline bases to make computations tractable while maintaining accuracy as good as smoothing splines. This paper extends penalized spline methodology by both modeling the variance...

Time series models relating short-term changes in air pollution levels to daily mortality counts typically assume that the effects of air pollution on the log relative rate of mortality do not vary with time. However, these short-term effects might plausibly vary by season. Changes in the...

Most markets are characterized by imperfections, mostly market power and limited information. Under these circumstances, intermediaries like real estate agents and insurance brokers play an important role in the economy by facilitating exchange between third parties. As specialized entities they...

Effizienz als Leitbild der Wettbewerbspolitik: Für einen more economic approach" Die jüngsten Reformen im Europäischen Wettbewerbsrecht geben Anlaß, sich erneut mit Grundsatzfragen der Wettbewerbspolitik zu beschäftigen. Unter Rückgriff auf die moderne Wettbewerbstheorie, die Industrie-...

In Economics, as in any social science, empirical tests of theoretical results face a problem: researchers are unable to reproduce the whole economy (or at least its relevant parts) in their laboratories. Nowadays, Experimental Economics uses stylized experiments, drawing on the experience of...

This is the first study that assesses the economic effects of direct democratic institutions on a cross country basis. Most of the results of the former intra-country studies could be confirmed. On the basis of some 30 countries, a higher degree of direct democracy leads to lower total...

The purpose of the paper is (1) to analyze the incentives for a vertically integrated input monopolist to engage in price-discrimination when there is downstream entry, and (2) to examine the question, whether a cost-based regulation of access charges for electricity grids enhances competition...