Symmetry and order in the portfolio allocation problem

Summary. This research studies the role of multivariate distribution structures on random asset returns in determining the optimal allocation vector for an expected utility maximizer. All our conclusions pertain for the set of risk averters. By carefully disturbing symmetry in the distribution of the, possibly covarying, returns, we ascertain the ordinal structure of the optimized allocation vector. Rank order of allocations is also established when a permutation symmetric random vector is mapped into the returns vector through location and scale shifts. It is shown that increased dispersion in the vectors of location and scale parameters benefit, ex-ante, investors as does a decrease in the rank correlation coefficient between the location and scale parameter vectors. Revealed preference comparative static results are identified for the location and scale vectors of asset returns. For most issues addressed, we arrive at much stronger inferences when a safe asset is available. Received: August 8, 2000; revised version: January 8, 2001     

Cognitive processing models in performance appraisal: evidence from the Malaysian education system

The effectiveness of the decision‐making process in appraisal has been of long‐standing interest. This paper reports the results of research exploring the extent to which those undertaking appraisals apply systematic processes to their decision‐making, represented in terms of the cognitive processing models applied by appraisers. Results of 22 cognitive mapping interviews exploring appraisal practice, undertaken with appraisers in the Malaysian education system, are described. The resultant cognitive maps have been explored for what they tell us about the cognitive processing models underlying appraisers' decision‐making. Results suggest that the practice of appraisal evidenced in interviews demonstrates the presence of cognitive processing that reflects theoretical cognitive processing models, although some differences are observed between less experienced and experienced appraisers' models. Implications from the interview findings for the practice of appraisal are identified.     

Introduction to the Policy Forum on Commonwealth–State Funding Arrangements

This article introduces the Policy Forum on funding arrangements between the Commonwealth and the States.     

Teaching New Product Development To Employed Adults

The purpose of this article is to report the lessons derived from broad practical experience in teaching new product development (NPD) to employed adults. My observations are importantly augmented by diverse comments from nine other service providers who also conduct and participate in similar NPD education. Our combined lessons summarize what works and what to be forewarned about. (“Those who cannot remember the past are condemned to repeat it.”– George Santayana.) We believe that what we have learned from our very different and extensive involvement can help several audiences: (1) others who offer or plan to offer and deliver NPD education – educators, service providers, or practitioners; (2) organizations that may wish to sponsor NPD training in any form; and (3) those who expect to participate as students in NPD seminars or courses. The article has four main sections, all of which are intended to provide pointers and helpful suggestions based on our collective experience. First is a discussion of issues concerning program set‐up and acceptance. Both sponsors and participants have important responsibilities for this, which are explained. Second is a discussion of practical issues specific to NPD education. The varieties of subject matter and support materials, format options, techniques to sustain interest, instructor characteristics, and client confidentiality are covered. Third is a discussion of practical logistic issues that apply to all adult education but with an emphasis on NPD. Advance warning of what can be and has been encountered may help you circumvent many avoidable problems. Fourth is a brief discussion about the future for NPD education. In this we speculate that the emergence of broadband Internet may provide a new modality, the effectiveness of which is still uncertain. An important insight for you to note is that we do not always do the same thing or approach teaching situations in the same way. What has worked for one of us may not have been effective for another or in another situation. In summary, the experiences we record should help you improve the delivery of NPD education or more efficiently benefit from participation in such training. © 2002 Elsevier Science Inc. All rights reserved.     

A MULTINOMIAL APPROXIMATION FOR AMERICAN OPTION PRICES IN LÉVY PROCESS MODELS

This paper gives a tree-based method for pricing American options in models where the stock price follows a general exponential Lévy process. A multinomial model for approximating the stock price process, which can be viewed as generalizing the binomial model of Cox, Ross, and Rubinstein (1979) for geometric Brownian motion, is developed. Under mild conditions, it is proved that the stock price process and the prices of American-type options on the stock, calculated from the multinomial model, converge to the corresponding prices under the continuous time Lévy process model. Explicit illustrations are given for the variance gamma model and the normal inverse Gaussian process when the option is an American put, but the procedure is applicable to a much wider class of derivatives including some path-dependent options. Our approach overcomes some practical difficulties that have previously been encountered when the Lévy process has infinite activity.     

Does Hedging Affect Firm Value? Evidence from the US Airline Industry

Does hedging add value to the firm, and if so, is the source of the added value consistent with hedging theory? We investigate jet fuel hedging behavior of firms in the US airline industry during 1992–2003 to examine whether such hedging is a source of value for these companies. We illustrate that the investment and financing climate in the airline industry conforms well to the theoretical framework of Froot, Scharfstein, and Stein (1993). In general, airline industry investment opportunities correlate positively with jet fuel costs, while higher fuel costs are consistent with lower cash flow. Given that jet fuel costs are hedgeable, airlines with a desire for expansion may find value in hedging future purchases of jet fuel. Our results show that jet fuel hedging is positively related to airline firm value. The coefficients on the hedging variables in our regression analysis suggest that the “hedging premium” is greater than the 5% documented in Allayannis and Weston (2001), and might be as large as 10%. We find that the positive relation between hedging and value increases in capital investment, and that most of the hedging premium is attributable to the interaction of hedging with investment. This result is consistent with the assertion that the principal benefit of jet fuel hedging by airlines comes from reduction of underinvestment costs.     

Analysis of Beef Producers' Risk Management Perceptions and Desire for Further Risk Management Education

Beef cattle producers were surveyed in Texas and Nebraska to investigate perceptions of sources of risk, the effectiveness of risk management strategies, and interest in further risk management education, particularly production risk, using probit analysis. Important decision variables identified are age, prior use of risk management tools, previous attendances of risk management education, and risk aversion. Severe drought and cattle price variability are identified as primary risk factors with potential to affect farm income. Extremely cold weather and disease are of less importance. Understocking pasture and storing hay are perceived most effective as risk management options.     

Predicting the geo-temporal variations of crime and disorder

Traditional police boundaries—precincts, patrol districts, etc.—often fail to reflect the true distribution of criminal activity and thus do little to assist in the optimal allocation of police resources. This paper introduces methods for crime incident forecasting by focusing upon geographical areas of concern that transcend traditional policing boundaries. The computerised procedure utilises a geographical crime incidence-scanning algorithm to identify clusters with relatively high levels of crime (hot spots). These clusters provide sufficient data for training artificial neural networks (ANNs) capable of modelling trends within them. The approach to ANN specification and estimation is enhanced by application of a novel and noteworthy approach, the Gamma test (GT).     

Engaged in battle: exploring the sources of workplace union militancy at Royal Mail

Sources of workplace union militancy at Royal Mail (UK) are examined in relation to four particular management initiatives in the late 1980s and 1990s. The wider industrial relations context and balance of power are emphasised and an assessment is made of the relative contribution of union leadership to workplace militancy.