Human Salmonellosis: Estimation of Dose-Illness from Outbreak Data

The quantification of the relationship between the amount of microbial organisms ingested and a specific outcome such as infection, illness, or mortality is a key aspect of quantitative risk assessment. A main problem in determining such dose-response models is the availability of appropriate data. Human feeding trials have been criticized because only young healthy volunteers are selected to participate and low doses, as often occurring in real life, are typically not considered. Epidemiological outbreak data are considered to be more valuable, but are more subject to data uncertainty. In this article, we model the dose-illness relationship based on data of 20 Salmonella outbreaks, as discussed by the World Health Organization. In particular, we model the dose-illness relationship using generalized linear mixed models and fractional polynomials of dose. The fractional polynomial models are modified to satisfy the properties of different types of dose-illness models as proposed by Teunis et al . Within these models, differences in host susceptibility (susceptible versus normal population) are modeled as fixed effects whereas differences in serovar type and food matrix are modeled as random effects. In addition, two bootstrap procedures are presented. A first procedure accounts for stochastic variability whereas a second procedure accounts for both stochastic variability and data uncertainty. The analyses indicate that the susceptible population has a higher probability of illness at low dose levels when the combination pathogen-food matrix is extremely virulent and at high dose levels when the combination is less virulent. Furthermore, the analyses suggest that immunity exists in the normal population but not in the susceptible population.     

Dramatically reducing cycle times through flash development

The reduction of cycle time has emerged as a fundamental element of new product development strategy. Many companies look solely at speed enhancement and increase the human, capital and technical resources allocated to development projects. However, additional resources do not guarantee significant reductions in cycle time. As well as speed enhancement activities, there exist two other sets of activities that are key to shortening the development cycle: those that act to prevent delays (friction) in the development process and those that define the scope of the final outcome (direction). This paper describes flash development as an alternative approach to reducing product development cycle times. Flash development works by creating a process that focuses on speed, friction and direction. The process is illustrated through an analysis of the Galileo Project at Nortel Networks.     

The paradox of multiple elections

Assume that voters must choose between voting yes (Y) and voting no (N) on three propositions on a referendum. If the winning combination is NYY on the first, second, and third propositions, respectively, the paradox of multiple elections is that NYY can receive the fewest votes of the 2³ = 8 combinations. Several variants of this paradox are illustrated, and necessary and sufficient conditions for its occurrence, related to the “incoherence” of support, are given. The paradox is shown, via an isomorphism, to be a generalization of the well-known paradox of voting. One real-life example of the paradox involving voting on propositions in California, in which not a single voter voted on the winning side of all the propositions, is given. Several empirical examples of variants of the paradox that manifested themselves in federal elections – one of which led to divided government – and legislative votes in the US House of Representatives, are also analyzed. Possible normative implications of the paradox, such as allowing voters to vote directly for combinations using approval voting or the Borda count, are discussed. Received: 31 July 1996 / Accepted: 1 October 1996     

The 2003 Heat Wave in France: Dangerous Climate Change Here and Now

In an analysis of the French episode of heat wave in 2003, this article highlights how heat wave dangers result from the intricate association of natural and social factors. Unusually high temperatures, as well as socioeconomic vulnerability, along with social attenuation of hazards, in a general context where the anthropogenic contribution to climate change is becoming more plausible, led to an excess of 14,947 deaths in France, between August 4 and 18, 2003. The greatest increase in mortality was due to causes directly attributable to heat: dehydration, hyperthermia, heat stroke. In addition to age and gender, combinatorial factors included preexisting disease, medication, urban residence, isolation, poverty, and, probably, air pollution. Although diversely impacted or reported, many parts of Europe suffered human and other losses, such as farming and forestry through drought and fires. Summer 2003 was the hottest in Europe since 1500, very likely due in part to anthropogenic climate change. The French experience confirms research establishing that heat waves are a major mortal risk, number one among so-called natural hazards in postindustrial societies. Yet France had no policy in place, as if dangerous climate were restricted to a distant or uncertain future of climate change, or to preindustrial countries. We analyze the heat wave's profile as a strongly attenuated risk in the French context, as well as the causes and the effects of its sudden shift into amplification. Research and preparedness needs are highlighted.     

Managerial Involvement and Perceptions of Strategy Process

Prior academic research attests to both positive and negative effects of involvement on the process of developing strategy. On the one hand, it has been argued that involvement strengthens shared vision, increases rationality and improves adaptiveness in strategy-making. On the other hand, involvement is said to lead to intense political behaviour, increased cultural inertia and more constraints in the strategy process. The purpose of this study is to investigate the relative importance of these effects. In a survey of over 6,000 managers, we find that their reported levels of involvement are positively associated with perceptions of strategy development processes that are more rational, more focused by a shared vision, and more adaptive. In addition, involvement is negatively associated with statements describing the process as top-down, influenced by politics and slowed by internal culture. Moreover, those who are more involved tend to see business and non-business constraints as less important in determining strategy. We argue that these associations between involvement and desirable features of strategy process are important because perceptions are the basis of managerial behaviour. Thus, managers who are more involved in strategy not only see the process in a more favourable light but also act in ways that make the process more effective. The main implication of these findings is that for most organisations increasing involvement improves the strategy process.     

The Blinders of Dominant Logic

This article argues that the dominant logic embedded in an organisation may keep it on the road ahead, but it also acts as a blinder to peripheral vision. It says that managers need to look at beyond the borders of their industries and geographies to find new opportunities and rethink the logic of the business. It refers to corporate examples where shifts in organisations’ dominant logic allowed traditional assumptions about value creation to be reassessed and resulted in successful forays into the periphery.     

Mining the Periphery for New Products

Revolutionary products often come from upstart players or companies outside the industry, while mainstream operators follow a risk-averse path of concentrating on their current business. This article urges companies to channel resources into looking at the periphery for ideas that could be profit-drivers of the future. It suggests three strategies for finding new products: frame the landscape; develop game-changing hypotheses; and use targeted hunting. It concludes by saying that these approaches will encourage managers to combine broad searching and thinking with focused evaluation and execution.     

Beyond Planning:: Strategies for Successfully Implementing Strategic Decisions

This article brings strategy back to managers and their organizations. It argues and demonstrates empirically that what managers do, and the kind of organization they lead, matter in terms of achieving stated objectives. Managerial action involves a set of activities from assessing the problem to prioritising action, and takes place within an organizational context which has two important elements for decision-making. First, organizations have an accumulated stock of experience, and the more managers can access and utilise this experience base the better. Secondly, the culture and structure of an organization may exhibit more or less readiness for the changes that decisions bring about, and contexts less ready for change pose problems for managers in the implementation of decisions.This long-term study of 55 decisions in UK firms shows that careful managerial planning does not of itself guarantee successful outcomes: the organizational context is crucial in framing actions and influencing achievement, and decisions may send a firm on a trajectory beyond the point at which it can plan with confidence. Where experience and readiness are strong, decisions achieve stated objectives—where both are lacking, decisions tend to fail. But, as examination of two illustrative cases indicates, strength in either domain may be enough: sound experience may win out in comparatively unreceptive situations, and decisions may still succeed where experience is lacking but the organization is ready for change. The article closes with some implications for managers.     

Social Loafing: A Field Investigation

Social loafing was investigated by testing a multilevel model among 23 intact work groups comprised of 168 employees representing two organizations. Results demonstrated that as hypothesized at the individual level, increases in task interdependence and decreases in task visibility and distributive justice were associated with greater occurrence of social loafing. At the group level, increased group size and decreased cohesiveness were related to increased levels of social loafing. Of particular interest was the finding that group member perceptions of perceived coworker loafing was associated with reduced social loafing, opposite of our predictions. We suggested that this unexpected finding may provide evidence of a social compensation effect.     

Volatility-based Effects on Shareholder Value: Alliance Activity in the Computing Industry

We use an event-study analysis to understand how alliance activity affects firm risk. The risk measure is the implied volatility of a firm’s stock price and the events are alliance announcements to the market. We build on the previous event-studies in the alliance literature that focus on the change in shareholder value by taking the first step in delineating what part of that value arises from the changes in the firm’s risk. The analysis reveals that a number of factors within a firm’s control can be used to manipulate risk exposure in an alliance, including the similarity of the firm’s and the alliance’s core activities, the governance form of the alliance, and the function of the alliance.