A modified false discovery rate multiple-comparisons procedure for discrete data, applied to human immunodeficiency virus genetics

Summary.  To help to design vaccines for acquired immune deficiency syndrome that protect broadly against many genetic variants of the human immunodeficiency virus, the mutation rates at 118 positions in HIV amino-acid sequences of subtype C versus those of subtype B were compared. The false discovery rate (FDR) multiple-comparisons procedure can be used to determine statistical significance. When the test statistics have discrete distributions, the FDR procedure can be made more powerful by a simple modification. The paper develops a modified FDR procedure for discrete data and applies it to the human immunodeficiency virus data. The new procedure detects 15 positions with significantly different mutation rates compared with 11 that are detected by the original FDR method. Simulations delineate conditions under which the modified FDR procedure confers large gains in power over the original technique. In general FDR adjustment methods can be improved for discrete data by incorporating the modification proposed.     

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.     

Composition-consistent tournament solutions and social choice functions

This paper introduces a new axiom for choice in preference profiles and tournaments, called composition-consistency. A social choice function is composition-consistent if it is non-sensitive to the cloning of one or several outcomes. The key feature of the composition consistency property is an operation concept called multiple composition product of profiles. The paper provides a brief overview of some social choice functions studied in the literature. Concerning the tournament solutions, it is proved that the Top Cycle, the Slater and the Copeland solutions are not composition-consistent, whereas the Banks, Uncovered Set, TEQ, Minimal Covering Set are composition-consistent. Moreover, we define the composition-consistent hull of a solution as the smallest composition-consistent solution containing . The composition-consistent hulls of the Top cycle and Copeland solutions are specified, and we give some hints about the location of the hull of the Slater set. Concerning social choice functions, it is shown that Kemeny, Borda and Minimax social choice functions are not composition-consistent, whereas the Paretian one is composition-consistent. Moreover, we prove that the latter is the composition-consistent hull of the Borda and Minimax functions.     

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.