The electronic ‘go-between service provider': a new ‘middle' role taking centre stage

While the full impact of the Internet on traditional business models and strategies is yet to be played out, one thing is already certain: it will irrevocably challenge the nature of the traditional middle role. A full spectrum of Internet-driven consequences — from disintermediation to cybermediation — has already been observed by numerous academics and practitioners. This article describes a different intermediary: the ‘go-between service provider,' who is increasingly challenging traditionalists benefiting from the new market and economic dynamics of our time. This paper, based on case studies and interviews as part of a long-term research project, presents a conceptual framework; lists critical success factors; and assesses the impact of all this on corporate thinking and practice.     

Strategic leadership and the chief executive

This article is based on research undertaken among South African chief executives occupying the most senior operational positions in public-quoted companies. In looking at distinctive characteristics in these individuals the research attempts to bring together the activities that shape the chief executive's job and explore possible trends in their background; career route and behaviour patterns, and from the compositie picture to provide guidelines for executive development.     

A comparison study of realtime fatality rates: severe acute respiratory syndrome in Hong Kong, Singapore, Taiwan, Toronto and Beijing, China

Summary.  In an outbreak of a completely new infectious disease like severe acute respiratory syndrome (SARS), estimation of the fatality rate over the course of the epidemic is of clinical and epidemiological importance. In contrast with the constant case fatality rate, a new measure, termed the 'realtime' fatality rate, is proposed for monitoring the new emerging epidemic at a population level. A competing risk model implemented via a counting process is used to estimate the realtime fatality rate in an epidemic of SARS. It can capture and reflect the time-varying nature of the fatality rate over the course of the outbreak in a timely and accurate manner. More importantly, it can provide information on the efficacy of a certain treatment and management policy for the disease. The method has been applied to the SARS data from the regions affected, namely Hong Kong, Singapore, Toronto, Taiwan and Beijing. The magnitudes and patterns of the estimated fatalities are virtually the same except in Beijing, which has a lower rate. It is speculated that the effect is linked to the different treatment protocols that were used. The standard estimate of the case fatality rate that was used by the World Health Organization has been shown to be unable to provide useful information to monitor the time-varying fatalities that are caused by the epidemic.     

Whom can you trust? The politics of ‘grassing’ on an inner city housing estate

This paper derives from an ongoing research project concerned to explore how people living in, going to work in, attending school in, high crime areas manage their routine daily lives. It focuses on one of our research areas in which we argue that the question of the 'fear of crime' is much better understood through an appreciation of how the question of trust manifests itself in that community. In other words, whom you trust, when, and by how much, mediate the way in which people living in this area manage their routine daily lives and within that their sense of security.     

Models of Neurotoxicity: Extrapolation of Benchmark Doses in Vitro

In risk assessment, no observed exposure level (NOAEL) and benchmark dose (BMD) are usually derived either from epidemiological studies in humans or from animal experiments. In many in vitro studies, concentration-effect/response curves have been analyzed using different mathematical models finalized to the identification of EC50. In the present article, we propose a model to fit dose-response curves in vitro. The BMD approach has been used to compare the cell viability (MIT assay) of different rat (C6 and PC12, glial and neuronal, respectively) and human cell lines (D384 and SK-N-MC, glial and neuronal, respectively) after 24-hour exposure to the following neurotoxic substances: manganese chloride (MnCl2), methyl-mercury (Me-Hg), and the enantiomers of styrene oxide (SO). For all rat and human cell lines, the potency of the examined compounds was: MnCl2 < S-SO < R-SO < Me-Hg. A preliminary comparison with in vivo toxicity data for these substances gave rise to consistent results. Whereas a reasonable agreement between in vitro and in vivo data has been found for Mn and styrene oxide, a wide scatter of LOAEL has been reported for Me-Hg and these appear to be either much higher or lower than the BMD for the MIT assay we observed in vitro.     

Dynamic factor models

Summary Factor models can cope with many variables without running into scarce degrees of freedom problems often faced in a regression-based analysis. In this article we review recent work on dynamic factor models that have become popular in macroeconomic policy analysis and forecasting. By means of an empirical application we demonstrate that these models turn out to be usefu in investigating macroeconomic problems.