In this paper we develop a unifying Markov-switching GARCH model which enables us (1) to specify complex GARCH equations in two distinct Markov-regimes, and (2) to model GARCH equations of different functional forms across the two Markov-regimes. To give a simple example, our flexible...

Using a Markov-switching GARCH model this paper analyzes the volatility evolution of the greenback's price in gold from after the Civil War until the return to gold convertibility in 1879. The econometric inference associated with our methodology indicates a switch to a regime of low volatility...

We present a new limit theorem for random means: if the sample size is not deterministic but has a negative binomial or geometric distribution, the limit distribution of the normalised random mean is a t-distribution with degrees of freedom depending on the shape parameter of the negative...

This paper is about the city size and growth rate distributions as seen from the perspectives of Zipf's and Gibrat's law. We demonstrate that the Gibrat and Zipf views are theoretically incompatible in view of the Fisher-Tippett theorem, and show that the conflicting hypotheses about the size...

New and old products differ in two respects: quality and newness. Whereas a higher quality of a new product always benefits consumers, the newness itself benefits some consumers, but not others, and for some, it is even a disadvantage. We capture these features in a Hotelling model of...

The recent introduction of new derivatives with future dividend payments as underlyings allows to construct a direct test of rational bubbles. We suggest a simple, new method to calculate the fundamental value of stock indices. Using this approach, bubbles become observable. We calculate the...

The authors develop a dynamic approach to measuring the evolution of comparative brand premium, an important component of brand equity. A comparative brand premium is defined as the pairwise price difference between two products being identical in every respect but brand. The model is based on...

A fundamental component of inter-temporal consumption-saving and portfolio allocation models is a statistical model of the income process. While income processes are commonly unobservable income flows which evolve in continuous time, observable income data are usually discrete, having been...

In case of herding, investors follow each other, prices move together more than they normally do, and the cross-sectional dispersion of returns decreases. Chang, Cheng, and Khorana (2000) suggest to test for herding by regressing the cross-sectional absolute deviation on the absolute and squared...

Recently various exchange rate models capturing the dynamics during the transition from an exchange rate arrangement of floating rates into a currency union have been derived. Technically, these stochastic equilibrium models are diffusion processes which have to be estimated by discretely...