Smoothing Sales Data by Progressive Correction

Het vloeiend volgen van verkoopcijfers door Progressieve Correctie.
Met een analogie tussen het vloeiend volgen - soms voorspellen genoemd - van een reeks verkoopcijfers en het automatisch regelen van een fysisch proces als leidraad wordt een nieuwe methode voor dit volgen getoond. De hieraan gegeven naam is: Volgen door Progressieve Correctie. De positie van deze methode t.o.v. "Exponential Smoothing" en de kwaliteitscontrole wordt aangeduid.     

Intellectual property rights and foreign direct investment: A disaggregated analysis

This paper aims at overcoming several shortcomings of previous empirical studies on the relationship between IPR protection and FDI. First of all, we use sectorally disaggregated FDI data for a large sample of host countries. Second, we address the proposition that stronger IPR protection raises not only the quantity but also the quality of FDI. Third, we check to which extent the relationship between IPR protection and FDI is affected by applying alternative measures of IPR protection. Our empirical findings support the hypothesis that the threat of an unauthorized use of intellectual-property-related assets and, thus, FDI depends on industry as well as host-country characteristics. Furthermore, stronger IPR protection may help induce high-quality FDI. JEL no. F21, F23     

On the microstructure of the german export boom: Evidence from establishment panel data, 1995–2002

This paper uses an unbalanced panel data set for exporting firms from manufacturing industries in one German federal state, Lower Saxony, to investigate the microstructure of the recent export boom. Looking at data for 1995/96–2001/02 it is demonstrated that a considerable number of plants start and stop exporting in each year, but that most of the export dynamics is due to positive and negative changes of exports in plants that continue exporting. A small fraction made of 4–5 percent of all exporting plants is responsible for around 70 to 80 percent of the gross increase in exports. Firms with expanding and contracting exports are found simultaneously in all broad sectors, technology classes and firm size classes. Patterns of export behavior differ widely between the plants over the periods investigated. JEL no. F14, E32     

Optimal portfolios when stock prices follow an exponential Lévy process

We investigate some portfolio problems that consist of maximizing expected terminal wealth under the constraint of an upper bound for the risk, where we measure risk by the variance, but also by the Capital-at-Risk (CaR). The solution of the mean-variance problem has the same structure for any price process which follows an exponential Lévy process. The CaR involves a quantile of the corresponding wealth process of the portfolio. We derive a weak limit law for its approximation by a simpler Lévy process, often the sum of a drift term, a Brownian motion and a compound Poisson process. Certain relations between a Lévy process and its stochastic exponential are investigated.Received: January 2003Mathematics Subject Classification: Primary: 60F05, 60G51, 60H30, 91B28; secondary: 60E07, 91B70JEL Classification: C22, G11, D81We would like to thank Jan Kallsen and Ralf Korn for discussions and valuable remarks on a previous version of our paper. The second author would like to thank the participants of the Conference on Lévy Processes at Aarhus University in January 2002 for stimulating remarks. In particular, a discussion with Jan Rosinski on gamma processes has provided more insight into the approximation of the variance gamma model.     

Seat allocation distributions and seat biases of stationary apportionment methods for proportional representation

In a proportional representation system, apportionment methods are used to round the vote proportion of a party to an integer number of seats in parliament. Assuming uniformly distributed vote proportions, we derive the seat allocation distributions for stationary divisor methods. An important characteristic of apportionment methods are seat biases, that is, expected differences between actual seat numbers and ideal shares of seats, when the parties are ordered from largest to smallest. We obtain seat bias formulas for the stationary divisor methods and for the quota method of greatest remainders.Acknowledgement. We thank Friedrich Pukelsheim for many fruitful discussions.Received March 2004