The limits of leverage

When trading incurs proportional costs, leverage can scale an asset's return only up to a maximum multiple, which is sensitive to its volatility and liquidity. In a model with one safe and one risky asset, with constant investment opportunities and proportional costs, we find strategies that maximize long‐term returns given average volatility. As leverage increases, rising rebalancing costs imply declining Sharpe ratios. Beyond a critical level, even returns decline. Holding the Sharpe ratio constant, higher asset volatility leads to superior returns through lower costs.     

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Book reviews

     

Values in Decision-Making Processes: Systematic Structures of J. Habermas and N. Luhmann for the Appreciation of Responsibility in Leadership

"Ethical Leadership" in modern multicultural corporations is first the consideration of different personal and cultural value systems in decision-making processes. Second, it is the assignment of responsibility either to individual or organisational causalities. The task of this study is to set the stage for a distinction between rational entities and the arbitrary preferences of individuals in economic decision making processes.Defining rational aspects of behaviour in economics will lead to the formal structures of organisational systems, which are independent of concrete but varying values. Luhmann's Theory of systems of communication describes the internal dynamic forces of economic communication processes in terms of formal structures. On the other hand Habermas' Theory of discourse integrates the previous relationship between individual subjectivity and rational behaviour. Habermas gives an indication of how to separate subjective values and meaning from rational arguments in rational communication processes. The translation of these theoretical structures into practical applications for decision making processes and decision taking acts links the ethical, or value-oriented, context precisely to both individual and organisational areas of responsibility.     

VFR tourism: the importance of university students as hosts

The role of university students in attracting friends and relatives as visitors to their place of study is examined. A questionnaire survey conducted at a UK university is presented in the context of general UK tourism and the visits to friends and relatives (VFR) sector in particular. It is demonstrated that universities represent large, frequently underestimated, generators of VFR tourism and that significant differences exist between the friends and the relatives' components. The paper draws concrete conclusions about the marketing opportunities and argues that the students themselves represent the most effective target for promotion efforts. It also points out possibilities for turning day visits into overnight stays, particularly in the relatives' segment. Copyright © 2007 John Wiley & Sons, Ltd.     

Why it Pays to Conceal: On the Optimal Timing of Acquiring Verifiable Information

Abstract. We consider optimal contracts when a principal has two sources to detect bad projects. The first one is an information technology without agency costs (IT_P), whereas the second one is the expertise of an agent subject to moral hazard, adverse selection and limited liability (IT_A). First, we show that the principal does not necessarily benefit from access to additional information and thereby may prefer to ignore it. Second, we discuss different timings of information release, i.e., a disclosure contract offered to the agent after the principal announced the result of IT_P , and a concealment contract where the agent exerts effort before IT_P is checked. We find that concealment is superior whenever the quality of IT_P is sufficiently low. Then, IT_P is almost worthless under a disclosure contract, while it can still be exploited to reduce the agent's information rent under concealment. If the quality of IT_P improves, disclosure can be superior as it allows to adjust the agent's effort to the updated expected quality of the project. However, even for a highly informative IT_P , concealment can be superior as it mitigates the adverse selection problem.