Combining Significance of Correlated Statistics with Application to Panel Data*

The inverse normal method, which is used to combine P‐values from a series of statistical tests, requires independence of single test statistics in order to obtain asymptotic normality of the joint test statistic. The paper discusses the modification by Hartung (1999, Biometrical Journal, Vol. 41, pp. 849–855) , which is designed to allow for a certain correlation matrix of the transformed P‐values. First, the modified inverse normal method is shown here to be valid with more general correlation matrices. Secondly, a necessary and sufficient condition for (asymptotic) normality is provided, using the copula approach. Thirdly, applications to panels of cross‐correlated time series, stationary as well as integrated, are considered. The behaviour of the modified inverse normal method is quantified by means of Monte Carlo experiments.     

Spatial mobility and competition for jobs: Some theory and evidence for Western Germany

This paper sheds new light on the role of regional labor market conditions for regional mobility. We study competition for vacant jobs along two dimensions – between employed and unemployed job searchers, and between resident and non-resident job searchers – within a simple matching framework. Evidence from estimating regional matching functions with data on job searchers disaggregated by previous employment status and regional provenance indicates that competition for jobs along both dimensions affects hiring. Tests of the theoretical predictions suggest that labor market conditions do determine regional mobility, but the countervailing effects of competition between employed and unemployed dilute mobility effects.     

Federal Monetary Policy: A Comment

We comment on an article published in this journal by Hefeker (2003) and reveal an inconsistency in his analysis of monetary policy in federal monetary unions. We clarify an implicit assumption in his model and show that even when this further assumption is met, Hefeker's (2003) claim that a pure majority vote by the regions and the central government results in a monetary authority consisting solely of regionally appointed governors is not generally valid in the context of his model.     

Profit sharing and firm size: The role of team production

This paper presents a model showing that profit sharing is subject to the 1/N problem in the case of independent worker productivity but not in the case of interdependent worker productivity. This implies the role of firm size on the likelihood of profit sharing will differ by the nature of the underlying technology. We test this implication using German establishment data and using a proxy for interdependent worker productivity. The results conform to the theory showing that firm size is associated with reduced profit sharing use when technology is independent but not when technology is interdependent.     

Unifying exotic option closed formulas

This paper aims to unify exotic option closed formulas by generalizing a large class of existing formulas and by setting a framework that allows for further generalizations. The formula presented covers options from the plain vanilla to most, if not all, mountain range exotic options and is developed in a multi-asset, multi-currency Black?CScholes model with time dependent parameters. It particular, it focuses on payoffs that depend on the distributions of the underlyings prices at multiple but set time horizons. The general formula not only covers existing cases but also enables the combination of diverse features from different types of exotic options. It also creates implicitly a language to describe payoffs that can be used in industrial applications to decouple the functions of payoff definition from pricing functions. Examples of several exotic options are presented, benchmarking the closed formulas?? performance against Monte Carlo simulations. Results show a consistent over performance of the closed formula reducing calculation time by double digit factors.     

TEAMWORK AND INTRA‐FIRM WAGE DISPERSION AMONG BLUE‐COLLAR WORKERS

Using data on a sample of manufacturing establishments in Germany, we find that the use of self‐managed teams is associated with increased intra‐firm wage inequality between skilled and unskilled blue‐collar workers. We also show that moderating factors play an important role. While teamwork interacts positively with employer‐provided further training and a production technology of the most recent vintage, it interacts negatively with the age of the establishment and the coverage by a collective bargaining agreement.