A simplified approach to modeling the co‐movement of asset returns

The authors propose a simplified multivariate GARCH (generalized autoregressive conditional heteroscedasticity) model (the S‐GARCH model), which involves the estimation of only univariate GARCH models, both for the individual return series and for the sum and difference of each pair of series. The covariance between each pair of return series is then imputed from these variance estimates. The proposed model is considerably easier to estimate than existing multivariate GARCH models and does not suffer from the convergence problems that characterize many of these models. Moreover, the model can be easily extended to include more complex dynamics or alternative forms of the GARCH specification. The S‐GARCH model is used to estimate the minimum‐variance hedge ratio for the FTSE (Financial Times and the London Stock Exchange) 100 Index portfolio, hedged using index futures, and compared to four of the most widely used multivariate GARCH models. Using both statistical and economic evaluation criteria, it was found that the S‐GARCH model performs at least as well as the other models that were considered, and in some cases it was better. © 2007 Wiley Periodicals, Inc. Jrl Fut Mark 27:575–598, 2007     

The ‘greening’ of tourism micro‐businesses: outcomes of focus group investigations in South East Cornwall

The response of micro‐businesses to sustainability issues, and their use of environmental management tools and systems, are often presented as simply scaled‐down versions of those of larger businesses in the small and medium‐sized enterprise (SME) sector as a whole. This paper presents the findings of a series of focus groups with the owners of tourism micro‐businesses in South East Cornwall about their awareness, understanding and adoption of sustainable tourism practices. The results reveal a complex and diverse response to the concept that resists such generalizations. A genuine need for measures to increase awareness and integrate sustainability issues within business practice is highlighted. Initiatives that do not account for the heterogeneity of the sector are likely to have only limited success. Copyright © 2003 John Wiley & Sons, Ltd. and ERP Environment.     

Creative teachers and creative teaching strategies

The purpose of this study is to explore the factors that influence creative teaching and to find out what effective strategies are used by three award‐winning teachers in the learning area of Integrated Activities. As creative thinking is crucial for the knowledge economy, it is essential that education serves its purpose in improving this important aspect. The methods used for data collection include in‐depth interview, focus group interview, classroom observation and content analysis. Three teachers with a GreaTeach Creative Instruction Award for creative teaching in the Integrated Activities field were selected as subjects. Results were acquired by analysing the interview content, the teaching plans, teachers’ reflection and the classroom observation videotapes. The study found that: the factors influencing creative teaching in Integrative Activities are (a) personality traits: persistence, willingness to develop, acceptance of new experiences, self‐confidence, sense of humour, curiosity, depth of ideas, imagination, etc.; (b) family factors: open and tolerant ways of teaching children, creative performance of parents, etc.; (c) experiences of growth and education: self‐created games and stories, brainstorming between classmates, etc.; (d) beliefs in teaching, hard work, motivation and (e) the administrative side of school organization. Among these factors, beliefs in teaching, hard work and motivation are the main aspects. The effective teaching strategies used by the awarded teachers are: student‐centred activities, a connection between teaching contents and real life, management of skills in class, open‐ended questions, an encouragement of creative thinking and use of technology and multimedia. Integrated Activities are closely connected to life experience and a basis for the development of creative thinking within education.     

Are movie theaters doomed? Do exhibitors see the big picture as theaters lose their competitive advantage?

After three straight years of decline, movie theaters in the US may have recently ended a period of crisis with an increase in annual admissions (+ 3%) in 2006. This article argues, however, that major problems are not over for the industry. Most movie theaters in the multiplex era have adopted a remarkably similar strategy, one which is also very vulnerable to recent trends such as the explosion of home cinema, pay TV, video-on-demand (VOD), discounting by mass merchandisers of DVDs, computer games, and the collapse of video windows. Just as technological convergence has created a challenge for movie theaters, as it has in the past, so too can new technologies and creative use of assets (combined with multiple target marketing) offer a counter measure for at least some movie theaters; at least, until the next challenge arises. What is unlikely to succeed is the status quo, especially when so many multiplexes offer the same format as their competitors, appear to adopt a narrow definition of what business they are in, and manifest a ‘one-size-should-fit-all’ approach to customers. The industry has employed differentiation and niche marketing much less than other industries. As the extensive variety of necessary strategies cannot comprehensively be explored herein, this article focuses on two new technologies from the IMAX Corporation, DMX and MPX, as an example of how a theater operator might counter audience declines.     

Business Ethics – to Teach Or Not to Teach?

While some studies have explored the effects of taking business ethics classes on business students, several shortcomings in them invite greater scrutiny of this critical issue (cf. Robertson, 1993). In contrast to previous research, this study more directly assesses the impact of taking business ethics class on ethical decisions made by future business executives. To determine if teaching business ethics modifies behaviors or behavioral intentions, the current study examines decisions made in ethical situations rather than inferring the same by measuring attitudes, values, etc. Furthermore, these were measured in three different business contexts: whistle blowing, recruitment, and industrial espionage, to enhance the generalizability of the findings. Finally, unlike most previous studies, a within-subject's design was chosen to eliminate confounds that may be caused by not controlling for individual differences (Glenn, 1992). The current results indicate that business ethics classes have minimal effect on ethical decision making in any of the three contexts investigated, empirically providing support for Wolfe's (1993) and Wynd and Mager's (1989) position that teaching business ethics may have limited benefits.     

Results of a Delphi survey in drawing up the input-output tables for Catalonia

This work presents the results of an ambitious and innovative use of the Delphi technique in supplying a quantitative economic model, specifically in the preparation of the Input-Output Tables for Catalonia (TIOC 2001). Using this technique for obtaining subjective information from experts comes forward as a valid and reliable option for improving the quality of the data with which the Input-Output tables are constructed, also providing further economic and social advantages. The application presented thus opens up an interesting field of development for this technique and also gives several contributions for appraising the execution of a Delphi exercise of this type.     

Trading networks with price-setting agents

In a wide range of markets, individual buyers and sellers trade through intermediaries, who determine prices via strategic considerations. Typically, not all buyers and sellers have access to the same intermediaries, and they trade at correspondingly different prices that reflect their relative amounts of power in the market. We model this phenomenon using a game in which buyers, sellers, and traders engage in trade on a graph that represents the access each buyer and seller has to the traders. We show that the resulting game always has a subgame perfect Nash equilibrium, and that all equilibria lead to an efficient allocation of goods. Finally, we analyze trader profits in terms of the graph structure — roughly, a trader can command a positive profit if and only if it has an “essential” connection in the network, thus providing a graph-theoretic basis for quantifying the amount of competition among traders.