Seemingly Unrelated Negative Binomial Regression

This paper discusses the specification and estimation of seemingly unrelated multivariate count data models. A new model with negative binomial marginals is proposed. In contrast to a previous model based on the multivariate Poisson distribution, the new model allows for over-dispersion, a phenomenon that is frequently encountered in economic count data. Semi-parametric estimation is possible if some of the assumption of the fully specified model are violated.     

Prospective NATO or EU membership and institutional change in transition countries1

This article quantifies the impact of incentives related to potential membership on institutional change as measured by the World Bank Governance Indicators. Based on a panel of 25 transition countries for the period from 1996 to 2008, we show that pre‐accession incentives provided by EU and NATO clearly matter for institutional development. In addition, path‐dependency determined by cultural norms may be overcome by economic liberalization, while foreign aid hampers institutional development.     

Health care reform and the number of doctor visits—an econometric analysis

This paper evaluates the German health care reform of 1997, using the individual number of doctor visits as outcome measure and data from the German Socio‐Economic Panel for the years 1995–1999. A number of modified count data models allow us to estimate the effect of the reform in different parts of the distribution. The overall effect of the reform was a 10% reduction in the number of doctor visits. The effect was much larger in the lower part of the distribution than in the upper part. Copyright © 2004 John Wiley & Sons, Ltd.     

(S,s)-adjustment Strategies and Hedging under Markovian Dynamics

We study the destabilizing effect of hedging strategies under Markovian dynamics with transaction costs. Once transaction costs are taken into account, continuous portfolio rehedging is no longer an optimal strategy. Using a non-optimizing (local in time) strategy for portfolio rebalancing, explicit dynamics for the price of the underlying asset are derived, focusing in particular on excess volatility and feedback effects of these portfolio insurance strategies. Moreover, it is shown how these latter depend on the heterogeneity of the insured payoffs. Finally, conditions are derived under which it may be still reasonable, from a practical viewpoint, to implement Black–Scholes strategies.     

On how buyback and remanufacturing strategies affect the profitability of spare parts supply chains

The purpose of this paper is to provide a case-based framework to offer insights on the opportunity of recovering parts. We consider a two-stage spare parts supply chain, where independent repair shops are responsible for handling the repair process. There are two options to meet spare parts demand: repair shops may replace the part with a new one (ordered from the OEM) or they may use a part that they themselves repaired before. While repair shops achieve a larger profit by repairing parts, the OEM would prefer the use of new parts. However, he has no control over demand which might be obtained by offering buyback of broken parts. Furthermore, the OEM could recover these parts on a higher level, thus reducing production/procurement of new parts. The main contribution of this paper is the provision of a simple deterministic framework for answering the question whether a buyback option should be offered by the OEM to the repair shops, and which buyback price should be paid for each returned core. We further highlight the impact of remanufacturing performed at the OEM on the profitability of buyback.     

Is there an equilibrating relationship between house prices and replacement cost? Empirical evidence from Berlin

It is a feature of competitive markets with forward-looking participants that a good’s benefit and its production cost are equalized in equilibrium and that no resources are wasted during the adjustment process. For housing markets, there is mixed evidence whether they meet this standard of allocative efficiency. Based on a unique data set with rich information on prices and cost, we examine the market for single-family houses in Germany’s capital Berlin. At the aggregate market level, we find that prices and cost tend to equalize in the long run. Short-run adjustment appears to be sufficiently fast and properly anticipated to prevent systematic excess profit opportunities. At the cross sectional level of individual houses, we find support that resources are allocated efficiently between different market segments. Taken together, our results provide sufficient evidence that the market in Berlin is efficient.