Robust min–max portfolio strategies for rival forecast and risk scenarios

We consider an extension of the Markowitz mean–variance optimization framework to multiple return and risk scenarios. It is well known that asset return forecasts and risk estimates are inherently inaccurate. The method proposed provides a means for considering rival representations of the future. The optimal portfolio is computed, simultaneously with the worst case, to take account of all rival scenarios. This is a min-max strategy which is essentially equivalent to a robust pooling of the scenarios. Robustness is ensured by the noninferiority of min–max. For example, a basic worst-case optimal return is guaranteed in view of multiple return scenarios. If robustness happens to have too high a cost, guided by the min–max pooling, it is also possible to explore other pooling alternatives. A min–max algorithm is used to solve the problem and illustrate the robust character of min–max with return and risk scenarios. We study the properties of the min–max risk–return frontier and compare with the potentially suboptimal worst-case where the investment strategy and the worst case are computed separately.     

Euro-currency market as recycling medium

During the past year the Euro-currency market played a very large role in bridging over the oil-induced payments imbalances. In the interest of international monetary stability this market should now move somewhat away from the centre of the stage and leave the main responsibility for the recycling of oil funds to the official financing mechanisms.     

Product-design perception and brand strength

In this article, we present an approach to understanding product design from a cognitive psychologist’s view. We show what cognitive processes are involved in perceiving products. Moreover, we discuss how these processes are related to the mental formation of brands and how they affect perceivers’ appreciation of a product’s design.     

Financial opening in developing countries

Many developing countries are currently considering liberalisation of external capital flows. While the ultimate objective of financial opening is to raise efficiency and growth, the reform process must be carefully designed to achieve these results. A recent conference has discussed the policy choices.     

The Research Field “Modeling Business Information Systems”

The research field “Modeling business information systems” has a long tradition in the scientific discipline of Business and Information Systems Engineering (BISE). The present paper highlights research shaping the research field, discusses challenges impairing the development of the research field in the coming years, and outlines elements of a future research agenda.