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91.
This paper studies how an overall fuzzy preference relation can be constructed in the compensatory context of the simple additive difference model, when imprecision on the trade-offs has to be taken into account. Three credibility indices of preferences are analysed and illustrated by a numerical example. Arguments are presented supporting the use of the third index, for which an interesting transitivity property (which was an open problem) is proved.  相似文献   
92.
给出了求解常系数线性齐次微分方程组和常系数线性齐次差分方程组的一个方法,指出了这两种方程组之间存在的一个有趣关系.  相似文献   
93.
The World Health Organization (WHO) diagnostic criteria for diabetes mellitus were determined in part by evidence that in some populations the plasma glucose level 2 h after an oral glucose load is a mixture of two distinct distributions. We present a finite mixture model that allows the two component densities to be generalized linear models and the mixture probability to be a logistic regression model. The model allows us to estimate the prevalence of diabetes and sensitivity and specificity of the diagnostic criteria as a function of covariates and to estimate them in the absence of an external standard. Sensitivity is the probability that a test indicates disease conditionally on disease being present. Specificity is the probability that a test indicates no disease conditionally on no disease being present. We obtained maximum likelihood estimates via the EM algorithm and derived the standard errors from the information matrix and by the bootstrap. In the application to data from the diabetes in Egypt project a two-component mixture model fits well and the two components are interpreted as normal and diabetes. The means and variances are similar to results found in other populations. The minimum misclassification cutpoints decrease with age, are lower in urban areas and are higher in rural areas than the 200 mg dl-1 cutpoint recommended by the WHO. These differences are modest and our results generally support the WHO criterion. Our methods allow the direct inclusion of concomitant data whereas past analyses were based on partitioning the data.  相似文献   
94.
This paper develops a model ofinter vivos gifts and bequests in a setting of moral hazard and adverse selection. Altruistic parents do not perfectly know how much effort their children make to earn their living, nor do they know their true level of ability.Inter vivos gifts take place prior to the realization of the children's earnings whereas at the moment of bequests, parents do observe them. We show that an optimal transfer policy generally uses a mix ofinter vivos gifts — deemed as more efficient — and bequests — deemed as more redistributive.We are thankful to Allessandro Cigno, Jacques Cremer, Claude d Aspremont and anonymous referees for their comments.Responsible editor: Alessandro Cigno  相似文献   
95.
Network analysis, a methodology derived from general systems' theory, can be utilized as a community mental health administrative-evaluation procedure. Evaluation parameters derived from analysis of patient data as they “flow” through a network of agency services, provide measures of systemic functioning. These parameters include “longest paths” and various ratio relationships as evaluation measures of service delivery. The limitations of network analysis are examined by means of conceptual analyses, and phenomena that emerged from research experience. The necessity for both quantitative and qualitative data to ensure a meaningful evaluation of mental health services is explained. Conclusions about the value of the network analysis approach are considered.  相似文献   
96.
Many government agencies have "constituents" who believe the agencies should hear and consider their needs and desires in establishing program priorities. This article describes how one involves interested constituents (consumers, industry, medical professionals, and state organizations) in the agency's annual priority-setting process. This participation has produced a number of beneficial results-some expected and some unexpected.  相似文献   
97.
本文明确了融资代建制的概念,将公共工程项目–项目融资–代建制联系起来,构建了公共工程项目融资代建制模式框架为:二个层次、三种管理和三项保证。进一步指出融资代建制是有中国特色的PFI,是公共工程项目建设管理的创新模式。  相似文献   
98.
This paper addresses no-wait or no-idle flow shop scheduling problems with deteriorating jobs, i.e., jobs whose processing times are an increasing function of their starting time. A simple linear deterioration function is assumed and some dominating relationships between machines can be satisfied. It is shown that for the problems to minimize makespan or weighted sum of completion time, polynomial algorithms still exist, although these problems are more complicated than the classical ones. When the objective is to minimize maximum lateness or maximum tardiness, the solutions of a classical version may not hold.  相似文献   
99.
异质产品供应链定价控制权与零售商横向兼并效应分析   总被引:1,自引:0,他引:1  
针对一部线性合约与供应商是否具有绝对定价控制权,比较分析零售商横向兼并集中度提高对消费者福利的影响.结果表明,(1)当供应商具有绝对定价控制权时,零售商横向兼并对消费者产生的影响取决于产品替代性程度大小:若替代性程度较高,则将产生有利影响,反之,将产生不利影响;(2)当供应商没有绝对定价控制权时,零售商横向兼并对消费者产生的影响取决于零售商兼并前的相对定价控制权强弱与兼并后的相对定价控制权增幅大小:若零售商在供应链中处于相对弱势地位,且零售商横向兼并使零售商的定价控制权增幅较大,则兼并将对消费者产生有利影响,否则,将对消费者产生不利影响.  相似文献   
100.
利用回归和构造动态投资组合方法,对中国股票市场1995 年7 月到2000 年12 月股票 月收益率、交易额、总市值及其财务数据进行分析,发现中国股票市场具有显著的交易额效应、 A 股比例效应、市值效应、账面市值比效应等. 这些效应有密切的相互关系,但不能用市场beta 值来解释. 市场beta 值、市值因子、账面市值比因子一起,也就是Fama2French 三因子模型,可以 很好地解释这些效应  相似文献   
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