After the End of History

Over the last century, the national approach has been the mainstream conception leading superpowers’ foreign policy, while the end of the Cold War brought about the worldwide multiplication of local conflicts. This differs from the past as this extensive international fragmentation urgently requires the adaptation of a new theoretical model to current international relations. This implies the re-consideration of some basic concepts such as national sovereignty, whose traditional fixed borders tend now to blur with a set of overlapping clusters of jurisdictional, economic, political, cultural interests.     

Diversity as width

It is argued that if a finite partially ordered population is given, and incomparability is taken as the relevant type of dissimilarity, then diversity comparisons between subpopulations may be conveniently based on widths namely on the maximum number of pairwise incomparable units they include. We introduce two width-based rankings. The first one is the plain width-ranking of subposets as induced by width computation. The second one is the undominated width-ranking of subposets namely the ranking induced by the sizes of undominated subposets. Simple axiomatic characterizations of the foregoing rankings are provided.     

Testing for boundary conditions in case of fractionally integrated processes

Statistical Methods & Applications - Bounded integrated time series are a recent development of the time series literature. In this paper, we work on testing the presence of unknown boundaries...     

Bayesian non-parametric inference for species variety with a two-parameter Poisson–Dirichlet process prior

Summary.  A Bayesian non-parametric methodology has been recently proposed to deal with the issue of prediction within species sampling problems. Such problems concern the evaluation, conditional on a sample of size n , of the species variety featured by an additional sample of size m . Genomic applications pose the additional challenge of having to deal with large values of both n and m . In such a case the computation of the Bayesian non-parametric estimators is cumbersome and prevents their implementation. We focus on the two-parameter Poisson–Dirichlet model and provide completely explicit expressions for the corresponding estimators, which can be easily evaluated for any sizes of n and m . We also study the asymptotic behaviour of the number of new species conditionally on the observed sample: such an asymptotic result, combined with a suitable simulation scheme, allows us to derive asymptotic highest posterior density intervals for the estimates of interest. Finally, we illustrate the implementation of the proposed methodology by the analysis of five expressed sequence tags data sets.     

The Insurance Industry in Jordan

This paper examines the structure and performance of the insurance industry in Jordan during the period of 2000–2005. The Jordanian insurance industry is free of state ownership in both primary insurance and reinsurance markets and has been spared the pervasive premium, product, investment, and reinsurance controls that have bedeviled the insurance markets of so many developing countries around the world. Despite these positive features, the insurance industry is not developed, which mainly reflects the underdevelopment of life insurance that has annual premiums of only 0.27 percent of GDP. In contrast, the level of general insurance is comparable to that of several other developing countries in the region. To overcome this situation a major modernization effort should be undertaken.      

Discussion of “On simulation and properties of the stable law” by L. Devroye and L. James

We contribute to the discussion of the paper by Devroye and James, by reviewing some of the most meaningful results that relate the unilateral stable distribution with the asymptotic behavior of the so-called Ewens-Pitman sampling model. Our focus is then on how these results have been exploited in the context of Bayesian nonparametric inference for species sampling problems.     

Using Electronic Contact to Reduce Homonegative Attitudes,Emotions, and Behavioral Intentions Among Heterosexual Women and Men: A Contemporary Extension of the Contact Hypothesis

The current study experimentally examined the potential for a contemporary extension of the contact hypothesis, known as electronic contact, or E-contact, to reduce sexual prejudice, intergroup anxiety, and avoidant behavioral intentions among heterosexuals. It also extended the sexual minority contact literature by examining the role of participant and interaction partner sex as a possible boundary condition of this contact–prejudice relationship. To test our hypotheses, 140 heterosexual female and male university students were randomly allocated to interact with a homosexual or heterosexual, female or male E-contact partner, in a collaborative and text-only online interaction before completing the outcome measures. Overall, the results demonstrated that interacting online with a female, as opposed to a male, homosexual E-contact partner reduced heterosexual men’s feelings of intergroup anxiety, which in turn was associated with lower sexual prejudice and outgroup avoidance. For heterosexual women, however, E-contact did not influence the outcome variables. In the context of sexual prejudice, these results suggest that E-contact may be particularly useful as a prejudice-reduction strategy among individuals who typically require it most: heterosexual men.