Theory predicts a positive relationship between market concentration and profitability in most scenarios. In empirical work, however, this relation is frequently not found or only a weak connection is observed. We compare the performance of concentration and market share variables, which are...

In this paper we derive nonparametric bounds for the cumulative incidence curve within a competing risks model with partly identified interval data. As an advantage over earlier attempts our approach also gives valid results in case of dependent competing risks. We apply our framework to...

We estimate the determinants of various types of product innovation. Knowledge spillovers from rivals have a positive impact on incremental innovations. This impact is largely independent of the participation in R&D cooperations. Spillovers exert no such independent influence on drastic...

We consider an extension of conventional univariate Kaplan-Meier type estimators for the hazard rate and the survivor function to multivariate censored data with a censored random regressor. It is an Akritas (1994) type estimator which adapts the nonparametric conditional hazard rate estimator...

This paper presents the results of an empirical test concerning the auction model of Gilbert and Newbery (1982). The study uses data on German companies in order to analyze expenditures for technology licenses. Aside of standard control variables the motives for innovation expenditures are also...

Economic theory suggests that an extension of the maximum length of entitlement for unemployment benefits increases the duration of unemployment. Empirical results for the reform of the unemployment compensation system in Germany during the 1980s are less clear. The analysis in this paper is...

In many situations the applied researcher wants to combine different data sources without knowing the exact link and merging rule. This paper considers different interpolation methods for interpolating attributes from German labor office districts to German counties and vice versa. In...

In this paper, we estimate the effect of different macro and micro variables on the distribution of unemployment duration in West Germany using censored quantile regressions. We analyze unemployment periods of more than 91,000 observations from the years 1981 to 1997 drawn from the IAB...

Consumption based equivalence scales are estimated by applying the extended partially linear model (EPLM) to the 1998 Income and Consumption Survey (EVS) carried out in Germany. In this model the equivalence scales are identified by virtue of nonlinearities in household demand. Therefore, the...