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51.
Time series of daily mean temperature obtained from the European Climate Assessment data set is analyzed with respect to their extremal properties. A time-series clustering approach which combines Bayesian methodology, extreme value theory and classification techniques is adopted for the analysis of the regional variability of temperature extremes. The daily mean temperature records are clustered on the basis of their corresponding predictive distributions for 25-, 50- and 100-year return values. The results of the cluster analysis show a clear distinction between the highest altitude stations, for which the return values are lowest, and the remaining stations. Furthermore, a clear distinction is also found between the northernmost stations in Scandinavia and the stations in central and southern Europe. This spatial structure of the return period distributions for 25-, 50- and 100-years seems to be consistent with projected changes in the variability of temperature extremes over Europe pointing to a different behavior in central Europe than in northern Europe and the Mediterranean area, possibly related to the effect of soil moisture and land-atmosphere coupling.  相似文献   
52.
In this paper, we study, by means of randomized sampling, the long-run stability of some open Markov population fed with time-dependent Poisson inputs. We show that state probabilities within transient states converge—even when the overall expected population dimension increases without bound—under general conditions on the transition matrix and input intensities.

Following the convergence results, we obtain ML estimators for a particular sequence of input intensities, where the sequence of new arrivals is modeled by a sigmoidal function. These estimators allow for the forecast, by confidence intervals, of the evolution of the relative population structure in the transient states.

Applying these results to the study of a consumption credit portfolio, we estimate the implicit default rate.  相似文献   

53.
Since the early 1960s, social support has been a topic of interest and study among social psychologists and other professionals investigating social issues. In spite of this growing interest by the scientific community, there are few studies on social support in the lesbian, gay, bisexual, and transgender (LGBT) community, and even fewer on the impact of social support on life satisfaction. In this regard, in Spain, there are very few psychosocial studies on homosexual groups. In the present study, the authors analyze social support data and life satisfaction in a sample of 220 gay residents of Málaga and Sevilla. The results show that friends are the most important source of overall social support, and that, in the family, sisters provide the most support and contribute to increased life satisfaction. On the other hand, social support had an effect on the level of life satisfaction, although the results indicate that factors associated with homosexual identity are the best predictors of life satisfaction. The implications of these results are discussed as well as potential future research.  相似文献   
54.
Many approaches to estimation of panel models are based on an average or integrated likelihood that assigns weights to different values of the individual effects. Fixed effects, random effects, and Bayesian approaches all fall into this category. We provide a characterization of the class of weights (or priors) that produce estimators that are first‐order unbiased. We show that such bias‐reducing weights will depend on the data in general unless an orthogonal reparameterization or an essentially equivalent condition is available. Two intuitively appealing weighting schemes are discussed. We argue that asymptotically valid confidence intervals can be read from the posterior distribution of the common parameters when N and T grow at the same rate. Next, we show that random effects estimators are not bias reducing in general and we discuss important exceptions. Moreover, the bias depends on the Kullback–Leibler distance between the population distribution of the effects and its best approximation in the random effects family. Finally, we show that, in general, standard random effects estimation of marginal effects is inconsistent for large T, whereas the posterior mean of the marginal effect is large‐T consistent, and we provide conditions for bias reduction. Some examples and Monte Carlo experiments illustrate the results.  相似文献   
55.
When a genetic algorithm (GA) is employed in a statistical problem, the result is affected by both variability due to sampling and the stochastic elements of algorithm. Both of these components should be controlled in order to obtain reliable results. In the present work we analyze parametric estimation problems tackled by GAs, and pursue two objectives: the first one is related to a formal variability analysis of final estimates, showing that it can be easily decomposed in the two sources of variability. In the second one we introduce a framework of GA estimation with fixed computational resources, which is a form of statistical and the computational tradeoff question, crucial in recent problems. In this situation the result should be optimal from both the statistical and computational point of view, considering the two sources of variability and the constraints on resources. Simulation studies will be presented for illustrating the proposed method and the statistical and computational tradeoff question.  相似文献   
56.
This study examines a Nicaraguan community 3 years after the signing of the Dominican Republic-Central American Free Trade Agreement (CAFTA). Qualitative and quantitative methods were used to learn how families, living in a community constructed near a US-owned factory, maintained resilience under growing negative conditions. These conditions relate to family dislocation, loss of support systems, lack of childcare, safe water, and food security, in addition to labor injustices. Although maintaining relatively high scores on a baseline resilience test, these families and others like them in Central America, demonstrate a struggle for survival in a globalized context.  相似文献   
57.
Book reviews     
New scholarship on rape in American history

Sex Without Consent: Rape and Sexual Coercion in America. Edited by Merril D. Smith. New York: New York University Press, 2001, 308 pages. Cloth, $60.00; paper, $19.50.

The enigma of sexual desire

Sexual Appetite, Desire and Motivation: Energetics of the Sexual System. Edited by Walter Everaerd, Ellen Laan, and Stephanie Both. Amsterdam, Netherlands: Knaw Edita, 2001, 156 pages. Paper, NLG 80.00, Euro 36.30.

American sex in the private and public sectors

Sex, Love, and Health in America: Private Choices and Public Policies. Edited by Edward O. Laumann and Robert T. Michael. Chicago, IL: The University of Chicago Press, 2000, 535 pages. Hardcover, $48.

Enlarging the landscape of sexual pleasure

Good Sex: Feminist Perspectives from the World's Religions. Edited by Patricia Beattie Jung, Mary E. Hunt, and Radhika Balakrishnan. New Brunswick, NJ: Rutgers University Press, 2001, 220 pages. Cloth, $50.00; paper, $20.00.

Another stab at sexual theory

The Role of Theory in Sex Research. Edited by John Bancroft. Bloomington, IN: Indiana University Press, 2000, 366 pages. Cloth, $49.95.  相似文献   
58.
As part of a broader study aimed at evaluating perceived alliance with service providers and level of satisfaction with services received, 103 monolingual Spanish speaking Hispanic women were interviewed. Participants were receiving ongoing behavioral health treatment at three different community service provider sites located in the greater New Haven area in Connecticut. These sites included a community health center (n = 40), a community behavioral health center (n = 40), and a faith-based agency (n = 23). As part of this study, the English version of the Therapeutic Alliance with Clinician (TAC) questionnaire was translated into Spanish and administered to our sample of Hispanic women. Results on the psychometric properties of the Spanish version of the TAC are presented in this article.  相似文献   
59.
In the new development strategy currently shaping Latin America, alternative social policy models have emerged. This article argues that far from being rival alternatives, each of these models considers the wide differences among countries. The region is emerging from a century of transformation – from a traditional agrarian economy to an urban industrial one – in which countries have taken diverse historical paths. Some have almost completed this transformation, others are taking early steps, and the vast majority are living through it. State‐led transition has followed two successive development strategies. From the 1920s up to the 1980s, state developmentalism has mostly successfully assumed the twin challenges of economic and social progress. In the last two decades of the century, Latin American states adopted the policies of the Washington Consensus, which emphasized the importance of business in the framework of globalization and benefited the affluent few. However, an unambiguous shift in direction has been taking place in Latin America since the 1997 economic crisis. This article suggests that a new developmental welfare state model seems to be in the making. How will it evolve over the wider space of an increasingly integrated Latin America?  相似文献   
60.
Innovation is nowadays a fundamental determinant of value creation in business companies and economic growth. Therefore, the measurement of innovation has become a significant concern both for business companies and governments. Traditionally, attempts to measure innovation have adopted a macroeconomic approach, as they have been largely based on broad surveys. However, no attempt has been made to date in order to complement the information provided by such surveys with aggregated data obtained from the financial reports of individual companies. This paper analyses the conceptual and methodological problems underlying the measurement of business innovation by means of surveys and discusses the lack of ability of accounting standards to accurately reflect innovative activities in the financial statements of business firms.In the light of the evidence provided by the empirical studies published to date, we analyse the Spanish situation by reviewing innovation studies conducted by the National Institute of Statistics (INE), and assessing the relationship between the value relevance of accounting information and the firm's technological level. Our results suggest that both, micro- and macroeconomic approaches towards the measurement of innovation have significant shortcomings. Thus, a joint effort seems to be needed in order to overcome the methodological limitations affecting innovation studies based on surveys and those relying on financial accounting information. Despite their limitations, surveys provide a sound basis for the identification of trends, key factors and explanatory variables. On the other hand, financial statements could provide a sound basis for the measurement of innovation if they included more relevant information on the intangible determinants of the value of companies. This has obvious implications for the standard setting process.  相似文献   
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