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981.
A distribution function is estimated by a kernel method with

a poinrwise mean squared error criterion at a point x. Relation- ships between the mean squared error, the point x, the sample size and the required kernel smoothing parazeter are investigated for several distributions treated by Azzaiini (1981). In particular it is noted that at a centre of symmetry or near a mode of the distribution the kernei method breaks down. Point- wise estimation of a distribution function is motivated as a more useful technique than a reference range for preliminary medical diagnosis.  相似文献   
982.
In recent years the analysis of interval-censored failure time data has attracted a great deal of attention and such data arise in many fields including demographical studies, economic and financial studies, epidemiological studies, social sciences, and tumorigenicity experiments. This is especially the case in medical studies such as clinical trials. In this article, we discuss regression analysis of one type of such data, Case I interval-censored data, in the presence of left-truncation. For the problem, the additive hazards model is employed and the maximum likelihood method is applied for estimations of unknown parameters. In particular, we adopt the sieve estimation approach that approximates the baseline cumulative hazard function by linear functions. The resulting estimates of regression parameters are shown to be consistent and efficient and have an asymptotic normal distribution. An illustrative example is provided.  相似文献   
983.
Book Reviews     
This article examines some difficulties associated with the Haynes–Stone model and attempts to clarify how the model can be justified as representing the hypothesis that “quantity is demand determined and price is supply determined.” It also argues that the applications of such a model as was done by Haynes and Stone might not have resolved the controversies related to the Phillips curve and the supply function of exports (or imports).  相似文献   
984.
There is neither a unified definition of disability nor a unique experience of disability across the world. The present paper aims to explore the lived experiences of disability in three different countries – Turkey, England and the USA – to evaluate the continued value of the social model of disability in those contexts. A comparison between these countries is provided through the lens of my personal experiences in each country as a disabled student and an academician. As can be seen in each example, whilst impairment does not change, the role of disabling barriers did change depending on the physical, social and psychological nature of the respective environments. We can therefore reasonably refer to the extent to which environments are disabling or non-disabling aspects of each setting. The paper provides a personal validation of the social nature of disability.  相似文献   
985.
This paper gives necessary and sufficient conditions for a mixed regression estimator to be superior to another mixed estimator. The comparisons are based on the mean square error matrices of the estimators. Both estimators are allowed to be biased.  相似文献   
986.
987.
In this paper, we consider the application of the empirical likelihood for

linear models under median constraints in view of robustness. For two simple median constraints, it is shown that conditions to ensure the consistency of the empirical likelihood confidence regions can be surprisingly relaxed compared with the normal approach under L norm. However, the coverage accuracy of the empirical likelihood confidence regions based on simple median constrains cannot be improved because of the discontinuity of the constraints. Therefore, a smoothed version of median constraint is proposed and a general theory is established to ensure its validity.  相似文献   
988.
ABSTRACT

This article provides an overview of spinal cord injury (SCI) that is useful and informative for social workers and other health care professionals who work with this population. Social workers new to the specialty of spinal cord injury must expand their knowledge base of this chronic injury. Social workers contribute to the rehabilitation process through assessment, education, and discharge planning. This article also may be used to inform persons with spinal cord injury and their families and to encourage them to engage in dialogue about SCI in the earliest stages of treatment and rehabilitation.  相似文献   
989.
Human-dominated ecosystems such as in South Florida's Everglades region are greatly affected by societal actions and choices, and efforts to restore degraded ecosystems must take into account the societal drivers of ecosystem change. A conceptual model of societal-ecological interactions within the region illustrates connections between major societal drivers, such as water management and land use, and ecological stressors, such as loss of habitat and nutrient loading. Using the conceptual model as an initial guide for discussion, examination of a restoration scenario for the region shows that social and economic effects from activities proposed in a restoration scenario will likely affect most sectors of South Florida. Political effects from changing land and water management practices likely will be significant, as will the physical effects of changing water structures and management practices. Conceptual models such as this can aid in the initial stages of ecosystem restoration discussions and can assist in planning for subsequent social science evaluations of specific societal impacts of actual proposed governmental restoration alternatives. In crafting restoration scenarios, local, regional, and national decision makers can use conceptual models such as this to help broaden the early considerations of how possible future changes in societal drivers, including management choices, will change ecological stressors that affect ecosystem health.  相似文献   
990.
A three-level growth-curve model was applied to estimate perceived impact growth trajectories, using multi-year data from project and school surveys on outcome and program implementation collected from 59 sites and approximately 1165 participating schools in the Safe Schools and Healthy Students Initiative. Primary interest is to determine whether and how project-level and school-level correlates affect schools’ perceptions of the Initiative's effectiveness over time when the effects of the pre-grant environmental conditions, grant operations, and near-term outcomes are considered. Coordination and service integration, comprehensive programs and activities for early childhood development, and change in school involvement were found to be significant predictors of school-perceived overall impact when the effect of poverty was considered. Partnership functioning, perceived importance of school resources, and school involvement were found to be significant predictors of school-perceived impact on substance use prevention when the effect of poverty was considered.  相似文献   
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