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721.
A comparative analysis of public sector restructuring in the U.S., Canada, Mexico, and the Caribbean
We examine public sector restructuring in North America and selected Commonwealth Caribbean nations. Although all the countries
studied experienced significant restruc-turing in response to public debt pressures, there were major differences across coun-tries
in the magnitude, pace, form, and the manner in which restructuring decisions were made. These differences reflect the state
of economic development and institu-tional characteristics, e.g., the role of the state and the industrial relations system.
In developing countries, international lending institutions played a major role in trans-forming the role of the state. In
developed countries, the inherent stability of the eco-nomic systems and institutional pressures led to a gradualist approach
to restructuring. 相似文献
722.
The area under the receiver operating characteristic curve (AUC) is the most commonly reported measure of discrimination for prediction models with binary outcomes. However, recently it has been criticized for its inability to increase when important risk factors are added to a baseline model with good discrimination. This has led to the claim that the reliance on the AUC as a measure of discrimination may miss important improvements in clinical performance of risk prediction rules derived from a baseline model. In this paper we investigate this claim by relating the AUC to measures of clinical performance based on sensitivity and specificity under the assumption of multivariate normality. The behavior of the AUC is contrasted with that of discrimination slope. We show that unless rules with very good specificity are desired, the change in the AUC does an adequate job as a predictor of the change in measures of clinical performance. However, stronger or more numerous predictors are needed to achieve the same increment in the AUC for baseline models with good versus poor discrimination. When excellent specificity is desired, our results suggest that the discrimination slope might be a better measure of model improvement than AUC. The theoretical results are illustrated using a Framingham Heart Study example of a model for predicting the 10-year incidence of atrial fibrillation. 相似文献
723.
Joseph J. Berest 《Journal of sex research》2013,50(3):210-219
While popular and psychoanalytic explanations of extramarital relations abound, no systematic sociological theory of such involvement has been presented to date. A partial theory of extramarital involvement is advanced in this paper. Based on the findings that the probability of involvement is related to socio‐economic status, the intensity of religious devoutness, residential background, premarital experience, the duration of marriage, level of marital satisfaction, and the degree of alienation, three propositions accounting for these relationships are set forth. On the basis of the theoretical propositions, the underlying dynamics of extramarital involvement are outlined and discussed. 相似文献
724.
A. B. Mettling 《Social Studies》2013,104(2):79-83
Abstract The movement for vocational education conceals within itself two mighty and opposing forces, one which would utilize the public school primarily to turn out more efficient laborers in the present economic regime, with certain incidental advantages to themselves, the other which would utilize all the resources of public education to equip individuals to control their own future economic careers, and thus help on such a reorganization of industry as will change it from a feudalistic to a democratic order. (Dewey 1917, 334-35) 相似文献
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In a longitudinal investigation of the antecedents and pathways of teen parenthood, 475 participants (248 females and 227 males) were followed from Grade 7 through early adulthood. In the first year of the investigation, homogeneous subgroups were identified by clustering participants on five characteristics (i.e., aggression, popularity, academic competence, age, and socioeconomic status). At the same time, peer social networks were identified by the Social Cognitive Map procedure. For each participant, the configuration of peer characteristics was also identified. A high correspondence was found between the individual characteristics and the characteristics of closely affiliated peers. Both teen fatherhood and teen motherhood were predicted by individual configurations and peer configurations (e.g., a combination of high aggression, low academic competence, low popularity, and low family SES). Peer characteristics, race, and family socioeconomic status assumed unique roles in predicting teen motherhood. Growth curve analyses showed that teen-mothers differed from non-mothers in their starting points and developmental trajectories. This study demonstrated that a simultaneous examination of both the individual and his/her peer context yielded important information on teen parenthood. 相似文献
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We consider some computational issues that arise when searching for optimal designs for pharmacokinetic (PK) studies. Special factors that distinguish these are (i) repeated observations are taken from each subject and the observations are usually described by a nonlinear mixed model (NLMM), (ii) design criteria depend on the model fitting procedure, (iii) in addition to providing efficient parameter estimates, the design must also permit model checking, (iv) in practice there are several design constraints, (v) the design criteria are computationally expensive to evaluate and often numerical integration is needed and finally (vi) local optimisation procedures may fail to converge or get trapped at local optima.We review current optimal design algorithms and explore the possibility of using global optimisation procedures. We use these latter procedures to find some optimal designs.For multi-purpose designs we suggest two surrogate design criteria for model checking and illustrate their use. 相似文献