On the equilibrium of voting games with abstention and several levels of approval

We study the core of “(j, k) simple games”, where voters choose one level of approval from among j possible levels, partitioning the society into j coalitions, and each possible partition facing k levels of approval in the output (Freixas and Zwicker in Soc Choice Welf 21:399–431, 2003). We consider the case of (j, 2) simple games, including voting games in which each voter may cast a “yes” or “no” vote, or abstain (j = 3). A necessary and sufficient condition for the non-emptiness of the core of such games is provided, with an important application to weighted symmetric (j, 2) simple games. These results generalize the literature, and provide a characterization of constitutions under which a society would allow a given number of candidates to compete for leadership without running the risk of political instability. We apply these results to well-known voting systems and social choice institutions including the relative majority rule, the two-thirds relative majority rule, the United States Senate, and the United Nations Security Council.     

On Variable Importance in Linear Regression

The paper examines in detail one particular measure of variable importance for linear regression that was theoretically justified by Pratt (1987), but which has since been criticized by Bring (1996) for producing “counterintuitive” results in certain situations, and by other authors for failing to guarantee that importance be non-negative. In the article, the “counterintuitive” result is explored and shown to be a defensible characteristic of an importance measure. It is also shown that negative importance of large magnitude can only occur in the presence of multicollinearity of the explanatory variables, and methods for applying Pratt's measure in such cases are described. The objective of the article is to explain and to clarify the characteristics of Pratt's measure, and thus to assist practitioners who have to choose from among the many methods available for assessing variable importance in linear regression.     

Confirmatory Factor Analysis of the Life Satisfaction Index

Factor models of the construct of well-being in later life have shown mixed results. Here we evaluated the factor structure of the Life Satisfaction Index A (LSIA), a widely used measure. Confirmatory factor analyses using a sample of community living aged people (N = 187) suggested that a unidimensional model was not appropriate for the scale. Moreover, only two of the 10 models previously proposed for the LSIA was found to fit reasonably well. These models (Bigot, 1974; Hoyt and Creech, 1983) consisted of only eight of the 20 LSIA items. Models which utilized all 20 LSIA items tended to fit poorly, whereas, those based on subsets of items generally showed improved fit. Allowing correlated factors also improved the fit. Throughout, fit indices were computed using the Satorra-Bentler scaled test statistic because the data were not normally distributed. These results highlight the importance of theory and construct development prior to actual scale development in social indicators research.     

Fallstudie: Optimierung des Arbeitsprozesses einer Arbeitsgruppe (Interventionswissenschaft in Aktion)Case study: work process optimisation of a working group (intervention science in action)

The paper describes an intervention research process within an organization. Goal of the research was to optimize the work process of a workgroup. A case study shows applied methods of intervention research in detail. Consideration of a combination of hierarchical organization and e.?g. project teams or workgroups provides the context of the paper. Inherent contradictions regarding hierarchical organization and workgroups and the involved challenges for employees are addressed.     

Bilinear modulation models for seasonal tables of counts

We propose generalized linear models for time or age-time tables of seasonal counts, with the goal of better understanding seasonal patterns in the data. The linear predictor contains a smooth component for the trend and the product of a smooth component (the modulation) and a periodic time series of arbitrary shape (the carrier wave). To model rates, a population offset is added. Two-dimensional trends and modulation are estimated using a tensor product B-spline basis of moderate dimension. Further smoothness is ensured using difference penalties on the rows and columns of the tensor product coefficients. The optimal penalty tuning parameters are chosen based on minimization of a quasi-information criterion. Computationally efficient estimation is achieved using array regression techniques, avoiding excessively large matrices. The model is applied to female death rate in the US due to cerebrovascular diseases and respiratory diseases.     

Statistical modelling of individual animal movement: an overview of key methods and a discussion of practical challenges

With the influx of complex and detailed tracking data gathered from electronic tracking devices, the analysis of animal movement data has recently emerged as a cottage industry among biostatisticians. New approaches of ever greater complexity are continue to be added to the literature. In this paper, we review what we believe to be some of the most popular and most useful classes of statistical models used to analyse individual animal movement data. Specifically, we consider discrete-time hidden Markov models, more general state-space models and diffusion processes. We argue that these models should be core components in the toolbox for quantitative researchers working on stochastic modelling of individual animal movement. The paper concludes by offering some general observations on the direction of statistical analysis of animal movement. There is a trend in movement ecology towards what are arguably overly complex modelling approaches which are inaccessible to ecologists, unwieldy with large data sets or not based on mainstream statistical practice. Additionally, some analysis methods developed within the ecological community ignore fundamental properties of movement data, potentially leading to misleading conclusions about animal movement. Corresponding approaches, e.g. based on Lévy walk-type models, continue to be popular despite having been largely discredited. We contend that there is a need for an appropriate balance between the extremes of either being overly complex or being overly simplistic, whereby the discipline relies on models of intermediate complexity that are usable by general ecologists, but grounded in well-developed statistical practice and efficient to fit to large data sets.     

Organizational responsiveness of Russian and American growth-oriented small and medium enterprises (SMEs)

The paper discusses problem-based learning (PBL) as a mediating factor in generating a variety of learning networks in workplace contexts. It is argued that informal learning in experiential circumstances can be systematized to encourage deep learning at the individual and collective level. Given the distinct problem-solving opportunities in PBL, learners can increase their capacity to acquire new knowledge through self-inquiry, reflection and dialogue. The repositioning of learning attitudes also leads to an enlargement of communities of practice wherein double and triple-loop learning cycles intersect to create rigorous learning. An integrated model is proposed to explain the dynamics of PBL operating within the constraints of workplace contexts.     

Explaining costumer reactions to real stockouts

The occurrence of stockouts remains an unsolved problem for retailers that provoke severe revenue and image losses, as well as greater customer dissatisfaction for both retailers and manufacturers. A literature review suggests a model of influential antecedents of consumers’ reactions to product unavailability. A field study then provides insights into true stockout situations, unlike a hypothetical research setting. With these data, this study reveals that loyalty and the presence of product alternatives have the greatest impacts on customer reactions. This result has significant theoretical and managerial implications due to the fact that results based on hypothetical settings did not hold.     

The global animus: in the tracks of world consciousness

In recent years, much has been made of the idea that under conditions of globalization, more and more people in different parts of the planet conceive of themselves as part of a ‘global society’ or ‘global culture’. Often it has been alleged that forms of consciousness centred around a disposition to see one's own life as a single part of the ‘world as a whole’ are relatively recent products. In this paper we argue that such tendencies, or something very much like them, in fact were present in the ancient Mediterranean world. We examine how ways of thinking and feeling, that bear in certain ways close correspondence to modern ideas as to ‘globality’, were prevalent amongst certain social groups in the Roman empire. Those persons regarded themselves as part of a world that was rapidly shrinking through increasing levels of political, commercial and other modes of interconnection between its geographically disparate parts. By examining these ancient attitudes, we demonstrate an important aspect of the pre-history of modern sensibilities as to the nature of a ‘globalizing/globalized world’. Moreover, by attending to ancient evidence as to ‘global’ attitudes and ‘global consciousness’, one may begin to overcome the presentism implicit in many contemporary accounts of globalization.