Detection of interactions in experiments on large numbers of factors

One of the main advantages of factorial experiments is the information that they can offer on interactions. When there are many factors to be studied, some or all of this information is often sacrificed to keep the size of an experiment economically feasible. Two strategies for group screening are presented for a large number of factors, over two stages of experimentation, with particular emphasis on the detection of interactions. One approach estimates only main effects at the first stage (classical group screening), whereas the other new method (interaction group screening) estimates both main effects and key two-factor interactions at the first stage. Three criteria are used to guide the choice of screening technique, and also the size of the groups of factors for study in the first-stage experiment. The criteria seek to minimize the expected total number of observations in the experiment, the probability that the size of the experiment exceeds a prespecified target and the proportion of active individual factorial effects which are not detected. To implement these criteria, results are derived on the relationship between the grouped and individual factorial effects, and the probability distributions of the numbers of grouped factors whose main effects or interactions are declared active at the first stage. Examples are used to illustrate the methodology, and some issues and open questions for the practical implementation of the results are discussed.     

A regional solution to the strategy and structure of multinationals

The transnational solution developed by Bartlett and Ghoshal is shown to be suitable for only a few special cases of multinational enterprise (MNE) strategy and structure. As MNEs have most of their assets and sales within their home region, they are in need of regional, not transnational strategy and structure. Here we provide data on the regional dimension of assets and sales of the world’s largest 500 multinationals. We explore how the empirical reality of a regional concentration of assets and sales imposes a regional solution, rather than the transnational solution.     

Demographic change, macroeconomic conditions, and the murder rate: The case of the United States, 1934–2006

Fluctuations in aggregate crime rates contrary to recent shifts in the age distribution of the U.S. population have cast doubt on the predictive power of the age–crime hypothesis. By examining a longer time horizon, back to the early 1930s, we show that the percentage of the young population is a robust predictor of the observed large swings in the U.S. murder rate over time. However, changes in the misery index—the sum of the inflation and unemployment rates—significantly contribute to explaining changes in the murder rate. This applies, in particular, to those changes that are at odds with the long-run trend of the U.S. age distribution, such as the decline in the murder rate in the latter part of the 1970s or its increase starting around the middle of the 1980s.     

Identifiable finite mixtures of location models for clustering mixed-mode data

For clustering mixed categorical and continuous data, Lawrence and Krzanowski (1996) proposed a finite mixture model in which component densities conform to the location model. In the graphical models literature the location model is known as the homogeneous Conditional Gaussian model. In this paper it is shown that their model is not identifiable without imposing additional restrictions. Specifically, for g groups and m locations, (g!)m–1 distinct sets of parameter values (not including permutations of the group mixing parameters) produce the same likelihood function. Excessive shrinkage of parameter estimates in a simulation experiment reported by Lawrence and Krzanowski (1996) is shown to be an artifact of the model's non-identifiability. Identifiable finite mixture models can be obtained by imposing restrictions on the conditional means of the continuous variables. These new identified models are assessed in simulation experiments. The conditional mean structure of the continuous variables in the restricted location mixture models is similar to that in the underlying variable mixture models proposed by Everitt (1988), but the restricted location mixture models are more computationally tractable.     

Project Success: A Multidimensional Strategic Concept

This article presents projects as powerful strategic weapons, initiated to create economic value and competitive advantage. It suggests that project managers are the new strategic leaders, who must take on total responsibility for project business results. Defining and assessing project success is therefore a strategic management concept, which should help align project efforts with the short- and long-term goals of the organization. While this concept seems simple and intuitive, there is very little agreement in previous studies as to what really constitutes project success. Traditionally, projects were perceived as successful when they met time, budget, and performance goals. However, many would agree that there is more to project success than meeting time and budget. The object of this study was to develop a multidimensional framework for assessing project success, showing how different dimensions mean different things to different stakeholders at different times and for different projects. Given the complexity of this question, a combination of qualitative and quantitative methods and two data sets were used. The analysis identified four major distinct success dimensions: (1) project efficiency, (2) impact on the customer, (3) direct business and organizational success, and (4) preparing for the future. The importance of the dimensions varies according to time and the level of technological uncertainty involved in the project. The article demonstrates how these dimensions should be addressed during the project’s definition, planning, and execution phases, and provides a set of guidelines for project managers and senior managers, as well as suggestions for further research.     

Heterosexual Masculinities,Anti‐homophobias,and Shifts in Hegemonic Masculinity: The Identity Practices of Black and White Heterosexual Men

In this study, I use in‐depth interview data with black and white heterosexual men to explore shifts in the role of homophobia in the social construction of heterosexual masculinities. A continuum is introduced to map a range of interactional practices through which these men enact heterosexual masculinities. Heterosexual men who, on one end of the continuum, construct their heterosexual masculinities through homophobic practices establish strong boundaries of social distance from gays. The other end documents heterosexual men's anti‐homophobias, moving from men who establish weak boundaries to those who blur them. These heterosexual men's anti‐homophobic stances trade on the prestige of being tolerant of gays, with black men's anti‐homophobias drawing on their experiences with racism.     

No Human Resource is an Island: Gendered,Racialized Access to Work as a Performer

This article explores the reproduction of gendered, racialized conceptions of age and appearance in structuring access to performing work. Analysis of this issue leads to discussion of a key supposition: that central work experiences of women performers are manifestations of their position as formal and informal proxies for women's experiences in wider society. Women performers are formal proxies in that they are employed to ‘be women’; to represent women for consumption in the circuit of culture. They are informal proxies in that they are allocated to highly segmented labour markets based on wider patterns of gendered, racialized social relations.