Probabilistic spatial power indexes

In this study, we present a generalization of spatial power indexes able to overcome their main limitations, namely (i) the excessive concentration of power measures; (ii) the too high sensitivity to players’ location in the ideological space. Voters’ propensity to support an issue is modeled via a random utility function with two additive terms: the deterministic term accounts for voters’ preference-driven/predictable behavior; the random one is a catch-all term that accounts for all the idiosyncratic/unpredictable factors. The relative strength of the two terms gives rise to a continuum of cases ranging from the Shapley value, where all aggregation patterns are equally probable, to a standard spatial value, like the Owen–Shapley index, where instead the conditional order is fully deterministic. As an illustrative application, we analyze the distribution of power in the Council of Ministers under three different scenarios: (i) EU15 Pre-Nice; (ii) EU27 Nice Treaty; (iii) EU27 Lisbon Treaty.     

Unit Root Tests under Time-Varying Variances

The paper provides a general framework for investigating the effects of permanent changes in the variance of the errors of an autoregressive process on unit root tests. Such a framework - which is based on a novel asymptotic theory for integrated and near integrated processes with heteroskedastic errors - allows to evaluate how the variance dynamics affect the size and the power function of unit root tests. Contrary to previous studies, it is shown that non-constant variances can both inflate and deflate the rejection frequency of the commonly used unit root tests, both under the null and under the alternative, with early negative and late positive variance changes having the strongest impact on size and power. It is also shown that shifts smoothed across the sample have smaller impacts than shifts occurring as a single abrupt jump, while periodic variances have a negligible effect even when a small number of cycles take place over a given sample. Finally, it is proved that the locally best invariant (LBI) test of a unit root against level stationarity is robust to heteroskedasticity of any form under the null hypothesis.     

Job Shop Scheduling With Deadlines

In this paper we deal with a variant of the Job ShopScheduling Problem. We consider the addition of release dates anddeadlines to be met by all jobs. The objective is makespanminimization if there are no tardy jobs, and tardiness minimizationotherwise. The problem is approached by using a Shifting Bottleneckstrategy. The presence of deadlines motivates an iterative use of aparticular one machine problem which is solved optimally. Theoverall procedure is heuristic and exhibits a good trade-off betweencomputing time and solution quality.     

Inhabitants' and Experts' Assessments of Environmental Quality for Urban Sustainability

In the context of sustainable urban development, we discuss the assessment of residential environmental quality and the importance of considering inhabitants' perceptions of natural resources in urban areas. Two series of studies, conducted in Guildford (United Kingdom) and in Rome (Italy), addressed the correspondence, or contrast, between inhabitants' and experts' assessment of urban quality concerning two crucial natural resources: air quality and biodiversity. The Guildford study emphasized the accuracy of the assessment of urban air quality by experts and the public. The Rome study focused on the evaluative criteria employed by scientists and the public in assessing the quality of urban green spaces. The results from both studies shed more, albeit complex, light on the simple conventional wisdom about public versus expert understanding and assessment of environmental quality. Study implications are discussed for the support of programs, methods, and tools for urban development, particularly with regard to effective communication and better structuring of residents' participation in urban environmental decision making.     

The management of firms’ alliance network positioning: Implications for innovation

In spite of the frequent calls for a much more integrated approach, the field of management still faces the ever continuing challenges in attempting to bridge the gap between academic research and managerial actions and practices. The field of strategic alliances and firms’ networks are those among which research and practice are more diverging. Trying to cover this separation, the article presents an empirical research on automotive industry that investigates the effects on innovation performance of the position that firms occupy in the network of alliances. The hypothesis that guides this research is that innovation is generated not only from the resources that a company is able to develop internally, but also through access to resources and capabilities owned by the external companies and organizations that the firm itself is tied to through alliances and cooperation agreements. Beyond this broad argument, the paper links tightly research and practice showing way and how the quality of access to resources owned by partners is influenced by the position occupied in the network of alliances and not only by the existence of single collaborative ties. Assuming a managerial approach which relies on the milestones of network research, different types of positioning in the network of alliances are discussed and tested on their impact on innovation.     

The Tempered Discrete Linnik distribution

We introduce a new family of integer-valued distributions by considering a tempered version of the Discrete Linnik law. The proposal is actually a generalization of the well-known Poisson–Tweedie law. The suggested family is extremely flexible since it contains a wide spectrum of distributions ranging from light-tailed laws (such as the Binomial) to heavy-tailed laws (such as the Discrete Linnik). The main theoretical features of the Tempered Discrete Linnik distribution are explored by providing a series of identities in law, which describe its genesis in terms of mixture Poisson distribution and compound Negative Binomial distribution—as well as in terms of mixture Poisson–Tweedie distribution. Moreover, we give a manageable expression and a suitable recursive relationship for the corresponding probability function. Finally, an application to scientometric data—which deals with the scientific output of the researchers of the University of Siena—is considered.     

Goodness-of-Fit Testing for the Newcomb-Benford Law With Application to the Detection of Customs Fraud

The Newcomb-Benford law for digit sequences has recently attracted interest in antifraud analysis. However, most of its applications rely either on diagnostic checks of the data, or on informal decision rules. We suggest a new way of testing the Newcomb-Benford law that turns out to be particularly attractive for the detection of frauds in customs data collected from international trade. Our approach has two major advantages. The first one is that we control the rate of false rejections at each stage of the procedure, as required in antifraud applications. The second improvement is that our testing procedure leads to exact significance levels and does not rely on large-sample approximations. Another contribution of our work is the derivation of a simple expression for the digit distribution when the Newcomb-Benford law is violated, and a bound for a chi-squared type of distance between the actual digit distribution and the Newcomb-Benford one.     

Two Strong Families in Southern Europe? Re-Examining the Geography of Kinship Regimes Stemming from the Reciprocity Mechanisms Between Generations

David Reher??s hypothesis of a specific pattern of ??strong family?? characterizing the south of Europe is currently widely shared. Is a further specification possible, one that applies uniquely to the Mediterranean family? The supporting evidence from a large corpus of in-depth interviews of young people aged 30?C34 and living in the north and south of Italy seems to confirm the existence of a dual identity for the strong family, located in two distinct belts within southern Europe divided along a north?Csouth gradient. Pointers to the historical and anthropological roots of this cleavage between the two southern family patterns are sought in two major texts, Ibn Kaldun??s Mouqaddima and Mauss?? ??Essay on the Gift.??