In view of the acceptance of short selling of stocks as an investment tool in the portfolio context by a growing number of institutional investors in recent years, the present study considers both normative and market-equilibrium aspects of portfolio selection with short selling. Under the full-information covariance structure of security returns, the study accurately captures institutional procedures for short selling without sacrificing analytical tractability. While short selling enhances the portfolio's risk-return trade-off from a normative perspective, the equilibrium analysis reveals that there is a continuum of market-clearing prices within two boundaries for each security. Economic implications of the equilibrium pricing relationship are also explored in the study.

The aim of our paper is to price credit derivatives written on a single name when this name is a bank. Indeed, due to the special structure of the balance sheet of a bank and to the interconnections with other institutions of the financial system, the standard pricing formulas do not apply and their use can imply severe mispricing. The pricing of credit derivatives written on a single bank name requires a joint analysis of the risks of all banks directly or indirectly interconnected with the bank of interest. Each name cannot be priced in isolation, but the banking system must be treated as a whole. It is necessary to analyze the contagion of losses among banks, especially the equilibrium of joint defaults and recovery rates at liquidation time. We show the existence and uniqueness of such an equilibrium. Then the standard pricing formulas are modified by adding a premium to capture the contagion effects.

This paper examines the performance of trend-following trading strategies in commodity futures markets using a monthly dataset spanning 48years and 28 markets. We find that all parameterizations of the dual moving average crossover and channel strategies that we implement yield positive mean excess returns net of transactions costs in at least 22 of the 28 markets. When we pool our results across markets, we show that all of the trading rules earn hugely significant positive returns that prevail over most subperiods of the data as well. These results are robust with respect to the set of commodities the trading rules are implemented with, distributional assumptions, data-mining adjustments and transactions costs, and help resolve divergent evidence in the extant literature regarding the performance of momentum and pure trend-following strategies that is otherwise difficult to explain.

This paper examines the relative efficiency of UK credit unions. Radial and non-radial measures of input cost efficiency plus associated scale efficiency measures are computed for a selection of input output specifications. Both measures highlighted that UK credit unions have considerable scope for efficiency gains. It was mooted that the documented high levels of inefficiency may be indicative of the fact that credit unions, based on clearly defined and non-overlapping common bonds, are not in competition with each other for market share. Credit unions were also highlighted as suffering from a considerable degree of scale inefficiency with the majority of scale inefficient credit unions subject to decreasing returns to scale. The latter aspect highlights that the UK Government's goal of larger credit unions must be accompanied by greater regulatory freedom if inefficiency is to be avoided. One of the advantages of computing non-radial measures is that an insight into potential over- or under-expenditure on specific inputs can be obtained through a comparison of the non-radial measure of efficiency with the associated radial measure. Two interesting findings emerged, the first that UK credit unions over-spend on dividend payments and the second that they under-spend on labour costs.

This paper presents a model of incentive compatible bank regulation under moral hazard and adverse selection. We derive a wide range of simple and conceptually implementable mechanisms that can solve each type of incentive problem separately and also achieve the first-best outcome – but only when regulatory instruments involve ex post pricing that is contingent on the bank's performance relative to the market. An important feature of these mechanisms is that they do not involve a subsidy to the bank. When the regulator faces both moral hazard and adverse selection simultaneously, we identify the conditions under which the same mechanism can achieve the first-best solution.