Several approaches for subset recovery and improved forecasting accuracy have been proposed and studied. One way is to apply a regularization strategy and solve the model selection task as a continuous optimization problem. One of the most popular approaches in this research field is given by...

Standard measures of consumer price inflation are based on a bundle of representative goods. It is well known that this approach might overstate inflation for new products and products with fast increasing quality. For this reason, hedonic adjustment methods have been proposed and introduced in...

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)....

We implement an endogeneous switching-regression model for labour productivity and firms' decision to use business-to-business (B2B) e-commerce. Our approach allows B2B usage to affect any parameter of the labour productivity equation and to properly take account of strategic complementarities...

This paper uses Granger non{causality tests to analyze if channel competition exists between the companion websites of 93 German newspapers observed between I/1998 and II/2005. It provides econometric evidence for significant negative effects of companion website tra?c on the print circulation...

This paper develops a three stage oligopoly game for R&D cooperation, R&D expenditure and product market competition. In the first stage, firms decide whether or not to conduct R&D in cooperation with other firms. In the second stage the level of R&D investment is determined. Finally, firms...

The macroeconomic development in West Germany in the aftermath of unification was characterized by a boom period in 1990/1991, a deep recession in 1992/1993 and a slow recovery since then. In East Germany, in contrast, unification induced a breakdown of production and employment followed by a...

Unification fundamentally changed the terms of quantitative macroeconomic analysis for Germany. Two main areas concerned are data availability for the eastern part of Germany and structural changes within the behavioural equations after unification. Our paper presents results from the estimation...

In an a priori view, it is usually assumed that the business cycle of manufacturing industries leads the business cycle of the service sector. This seems to be even more plausible for the relationship between business-related services, whose high growth rates in recent years were largely due to...

We analyze the performance of firms in the German business-related services sector. A quarterly business survey provides the panel data base of our study. Firm performance is measured by the survey respondents? ordinal indication of their changes in total sales. We use a firstorder Markov chain...