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161.
We show that, contrary to widespread belief, low-pay workers do not generally prefer that the minimum wage rate be increased until the labor demand is unitary elastic. Rather, there exists a critical value of elasticity of labor demand so that increases in the minimum wage rate make low-pay workers better off for higher elasticities, but worse off for lower elasticities. This critical value decreases with unemployment benefits and increases with workers’ risk aversion. We also show that in some countries the benefits for long-term unemployed are so low that workers would probably prefer that the minimum wage rate be decreased. I thank the anonymous referees for helpful suggestions.  相似文献   
162.
A framework for time varying parameter regression models is developed and employed in modeling and forecasting price expectations, using the Livingston data. Alternative model formulations, which include various choices for both the stochastic processes generating the varying parameters and the sets of explanatory variables, are examined and compared by using this framework. These models, some of which have appeared elsewhere and some of which are new, are estimated and used to assess the expectations formation process.  相似文献   
163.
基于对铁路货运站市场营销策略的分析,采用结构化设计和PowerBuilder 6.5程序设计的方法,对铁路货运站营销分析系统进行了规划与设计.该系统是在进行货运市场份额调查的基础上,建立货主信息库,通过实施客户经理制,对货运市场进行需求分析.为计算机辅助铁路市场营销决策的研究开拓了新的天地.  相似文献   
164.
The authors establish the joint distribution of the sum X and the maximum Y of IID exponential random variables. They derive exact formuli describing the random vector (X, Y), including its joint PDF, CDF, and other characteristics; marginal and conditional distributions; moments and related parameters; and stochastic representations leading to further properties of infinite divisibility and self-decomposability. The authors also discuss parameter estimation and include an example from climatology that illustrates the modeling potential of this new bivariate model.  相似文献   
165.
大学生是祖国的未来,为国家培养宝贵人才是每个教师的重任。在我国教育改革的洪流下。一线教师应充分掌握和利用先进的教学方法和教学资源。作者盼望通过本文能够与广大教育教学工作者们进行学术交流.为国家培养更多、更优秀的人才。  相似文献   
166.
SUMMARY

This article will focus on the research exploring the degree to which organizational integration of Employee Assistance, Work/Family and Wellness Programs has evolved since the early 1990s. The first study reviewed is the National Study of EAP and Work/Family Programs conducted in 1994 by Boston University's Center on Work and Family in which 100 of the top family friendly companies were inter viewed. Two major studies conducted under the guidance of the Employee Assistance Professional Association (EAPA) are then reviewed. The Phase I research conducted in 2001 was a large-scale survey of the professionals in fields of EAP and Work-life (N = 950). The Phase II research conducted in 2002 was comprised of two stages: A pilot study surveying vendors in the EAP and Work-life fields (N = 213) and a qualitative study consisting of in-depth interviews with vendors from all three professions (N = 79). The overall theme from this body of research is one of dramatically increasing movement and market demand for some form of collaboration/integration of service delivery. Finally, the chapter offers recommendations for further research regarding integration of services as well as implications for the professional fields.  相似文献   
167.
Multi-criteria inventory classification groups inventory items into classes, each of which is managed by a specific re-order policy according to its priority. However, the tasks of inventory classification and control are not carried out jointly if the classification criteria and the classification approach are not robustly established from an inventory-cost perspective. Exhaustive simulations at the single item level of the inventory system would directly solve this issue by searching for the best re-order policy per item, thus achieving the subsequent optimal classification without resorting to any multi-criteria classification method. However, this would be very time-consuming in real settings, where a large number of items need to be managed simultaneously.

In this article, a reduction in simulation effort is achieved by extracting from the population of items a sample on which to perform an exhaustive search of best re-order policies per item; the lowest cost classification of in-sample items is, therefore, achieved. Then, in line with the increasing need for ICT tools in the production management of Industry 4.0 systems, supervised classifiers from the machine learning research field (i.e. support vector machines with a Gaussian kernel and deep neural networks) are trained on these in-sample items to learn to classify the out-of-sample items solely based on the values they show on the features (i.e. classification criteria). The inventory system adopted here is suitable for intermittent demands, but it may also suit non-intermittent demands, thus providing great flexibility. The experimental analysis of two large datasets showed an excellent accuracy, which suggests that machine learning classifiers could be implemented in advanced inventory classification systems.  相似文献   

168.
In a clinical trial with the time to an event as the outcome of interest, we may randomize a number of matched subjects, such as litters, to different treatments. The number of treatments equals the number of subjects per litter, two in the case of twins. In this case, the survival times of matched subjects could be dependent. Although the standard rank tests, such as the logrank and Wilcoxon tests, for independent samples may be used to test the equality of marginal survival distributions, their standard error should be modified to accommodate the possible dependence of survival times between matched subjects. In this paper we propose a method of calculating the standard error of the rank tests for paired two-sample survival data. The method is naturally extended to that for K-sample tests under dependence.  相似文献   
169.
Interdependency analysis in the context of this article is a process of assessing and managing risks inherent in a system of interconnected entities (e.g., infrastructures or industry sectors). Invoking the principles of input-output (I-O) and decomposition analysis, the article offers a framework for describing how terrorism-induced perturbations can propagate due to interconnectedness. Data published by the Bureau of Economic Analysis Division of the U.S. Department of Commerce is utilized to present applications to serve as test beds for the proposed framework. Specifically, a case study estimating the economic impact of airline demand perturbations to national-level U.S. sectors is made possible using I-O matrices. A ranking of the affected sectors according to their vulnerability to perturbations originating from a primary sector (e.g., air transportation) can serve as important input to risk management. For example, limited resources can be prioritized for the "top-n" sectors that are perceived to suffer the greatest economic losses due to terrorism. In addition, regional decomposition via location quotients enables the analysis of local-level terrorism events. The Regional I-O Multiplier System II (RIMS II) Division of the U.S. Department of Commerce is the agency responsible for releasing the regional multipliers for various geographical resolutions (economic areas, states, and counties). A regional-level case study demonstrates a process of estimating the economic impact of transportation-related scenarios on industry sectors within Economic Area 010 (the New York metropolitan region and vicinities).  相似文献   
170.
浅谈书籍设计的人性化   总被引:1,自引:0,他引:1  
“人性化设计”已成为 2 1世纪设计的主题。书籍设计作为视觉传达的重要门类也将遵循以人为本的理念。通过书籍封面、插图、版式、文字、材料等元素用设计语言概括书的本质 ,形象地反映书的知识要义和思想精髓 ,强调理性的秩序 ,准确传达知识和思想 ,使之理性的内涵和感性的外延相结合 ,成为读者获取知识、陶冶情操的桥梁  相似文献   
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