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81.
This paper reports on the joint SPM/CRANEC Catholic University of Milan symposium on “World Development and the Restructuring of Industrial Economies” held at Bellagio, Lake Como, Italy during the week of 10–15 September 1979. The symposium was organized to discuss the adjustments required by the industrialized economies when adapting to the changes inherent in present world development trends, as well as to help define national and international policy measures that might be used to facilitate the restructuring process. This report reviews the key issues, alternative strategies for restructuring, and policy measures for restructuring discussed at the symposium. It also offers some conclusions based on the results of the symposium.  相似文献   
82.
83.
Optimal three-stage designs with equal sample sizes at each stage are presented and compared to fixed sample designs, fully sequential designs, designs restricted to use the fixed sample critical value at the final stage, and to modifications of other group sequential designs previously proposed in the literature. Typically, the greatest savings realized with interim analyses are obtained by the first interim look. More than 50% of the savings possible with a fully sequential design can be realized with a simple two-stage design. Three-stage designs can realize as much as 75% of the possible savings. Without much loss in efficiency, the designs can be modified so that the critical value at the final stage equals the usual fixed sample value while maintaining the overall level of significance, alleviating some potential confusion should a final stage be necessary. Some common group sequential designs, modified to allow early acceptance of the null hypothesis, are shown to be nearly optimal in some settings while performing poorly in others. An example is given to illustrate the use of several three-stage plans in the design of clinical trials.  相似文献   
84.
Adaptations are psychological and behavioral mechanisms designed through evolution to serve specific purposes ultimately related to reproductive success. Although adaptations are inherently functional, in some cases their operation can nevertheless cause personal and social dysfunction. We describe a theoretical framework for understanding, predicting, and reducing the dysfunctional consequences of psychological adaptations. We discuss three general sources of dysfunction: a) the existence of adaptive tradeoffs, b) mismatches between current environments and ancestral environments, and c) individual differences. The paper applies this framework primarily to the topic of social anxiety, a psychological phenomenon marked by concerns pertaining to social rejection and embarrassment. Although social anxiety can serve useful functions, it can also involve excessive worry, negative affect, and avoidance of social situations, leading to significant distress and social impairment. We consider sources of dysfunction in social anxiety and discuss implications for policy, including recommendations for psychological, situational, and biological interventions. We also discuss broader applications of this theoretical framework to other areas of social life.  相似文献   
85.
作为世界制造中心,深圳被联合国教科文组织授予"设计之都"的称号是理所应当的,而这一殊荣又能帮助深圳提高国际知名度.对于深圳来讲,要成为世界领先的设计之都,实际上可以采取很多种途径.  相似文献   
86.
In biomedical studies where the event of interest is recurrent (e.g., hospitalization), it is often the case that the recurrent event sequence is subject to being stopped by a terminating event (e.g., death). In comparing treatment options, the marginal recurrent event mean is frequently of interest. One major complication in the recurrent/terminal event setting is that censoring times are not known for subjects observed to die, which renders standard risk set based methods of estimation inapplicable. We propose two semiparametric methods for estimating the difference or ratio of treatment-specific marginal mean numbers of events. The first method involves imputing unobserved censoring times, while the second methods uses inverse probability of censoring weighting. In each case, imbalances in the treatment-specific covariate distributions are adjusted out through inverse probability of treatment weighting. After the imputation and/or weighting, the treatment-specific means (then their difference or ratio) are estimated nonparametrically. Large-sample properties are derived for each of the proposed estimators, with finite sample properties assessed through simulation. The proposed methods are applied to kidney transplant data.  相似文献   
87.
88.
We consider parametric non-linear regression models with additive innovations which are serially uncorrelated but not necessarily independent, and consider the consequences of maximum likelihood and related one-step iterative estimation when the innovations are treated as being iid from their unconditional density. We find that the estimators' asymptotic covariance matrices will generally differ from those that would obtain if the errors actually were iid, except for the special case of strictly exogenous regressors. One important application of these results is to analysis of the properties of adaptive estimators, which employ nonparametric kernel estimates of the unconditional density of the disturbances in the construction of one-step iterative estimators. In the presence of strictly exogenous regressors, adaptive estimators are found to be asymptotically equivalent to the one-step iterative estimators that use the correct unconditional density. We illustrate our results through a brief Monte Carlo study.  相似文献   
89.
The implications of environmental change for migration are little understood. Migration as a response to climate change could be seen as a failure of in situ adaptation methods, or migration could be alternatively perceived as a rational component of creative adaptation to environmental risk. This paper frames migration as part of an adaptation response to climate change impacts to natural resource condition and environmental hazards. Thresholds will be reached by communities after which migration will become a vital component of an effective adaptation response. Such changes to migration patterns have the potential to undermine migration policy unless appropriate preparations are undertaken. This paper describes an approach to assist researchers to frame how climate change will influence migration by critically analysing how thresholds of fundamental change to migration patterns could be identified, primarily in relation to two case studies in Nepal and Thailand. Future policy for internal and international migration could be guided by the analysis of such thresholds of non-linear migration and resourced effectively to ensure that socio-economic and humanitarian outcomes are maximised.  相似文献   
90.
Doctoral education is greatly impacted by context, and the large majority of marital and family therapy (MFT) doctoral programs are PhD programs in research-focused universities. I believe their primary mission is to equip students to become scientist–practitioners and do original research that will advance the science of the discipline, whereas the mission of the typical master’s program is to produce strong practitioners who are research informed. It is the emphasis on the scientific method, not the content specialty area, that should be the hallmark of PhD programs in research-focused contexts. I describe metrics for success that include not only research productivity but also the development of a supportive, open, flexible, and generous program culture. The research mission of these programs has been only modestly helped by the Commission on Accreditation for Marriage and Family Therapy Education process and the programs are largely not doing the programmatic intervention research that the field needs. As the universities that house these programs are also “raising the bar,” the long-term viability of the programs themselves will likely hinge on success in this arena.  相似文献   
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