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41.
In this paper, we present a general formulation of an algorithm, the adaptive independent chain (AIC), that was introduced in a special context in Gåsemyr et al . [ Methodol. Comput. Appl. Probab. 3 (2001)]. The algorithm aims at producing samples from a specific target distribution Π, and is an adaptive, non-Markovian version of the Metropolis–Hastings independent chain. A certain parametric class of possible proposal distributions is fixed, and the parameters of the proposal distribution are updated periodically on the basis of the recent history of the chain, thereby obtaining proposals that get ever closer to Π. We show that under certain conditions, the algorithm produces an exact sample from Π in a finite number of iterations, and hence that it converges to Π. We also present another adaptive algorithm, the componentwise adaptive independent chain (CAIC), which may be an alternative in particular in high dimensions. The CAIC may be regarded as an adaptive approximation to the Gibbs sampler updating parametric approximations to the conditionals of Π.  相似文献   
42.
我国产业间波及效应的探讨   总被引:2,自引:0,他引:2  
从理论上来说,某一产业的变化会引起其它产业间的连锁反映。产业间的波及效应可以通过投入系数表来加以分析。通过实证分析,研究我国产业间波及效应的强弱,可以为国家制定产业政策、优化产业结构提供依据。  相似文献   
43.
Abstract A model is introduced here for multivariate failure time data arising from heterogenous populations. In particular, we consider a situation in which the failure times of individual subjects are often temporally clustered, so that many failures occur during a relatively short age interval. The clustering is modelled by assuming that the subjects can be divided into ‘internally homogenous’ latent classes, each such class being then described by a time‐dependent frailty profile function. As an example, we reanalysed the dental caries data presented earlier in Härkänen et al. [Scand. J. Statist. 27 (2000) 577], as it turned out that our earlier model could not adequately describe the observed clustering.  相似文献   
44.
企业附加价值链表征企业文化的浓缩 ,是企业发展的生命线。企业附加价值链清晰、完备与否 ,是剖析企业存在、发展的根本之所在 ,也是考查、评价企业现状的基本依据。  相似文献   
45.
作为邓小平理论萌芽的标志不是某一具体的时间、论著、观点。对邓小平理论萌芽应作出系统的、全面的科学界定。邓小平理论萌芽的标志应该是时间段、论著链、观点网  相似文献   
46.
Abstract.  A Markov property associates a set of conditional independencies to a graph. Two alternative Markov properties are available for chain graphs (CGs), the Lauritzen–Wermuth–Frydenberg (LWF) and the Andersson–Madigan– Perlman (AMP) Markov properties, which are different in general but coincide for the subclass of CGs with no flags . Markov equivalence induces a partition of the class of CGs into equivalence classes and every equivalence class contains a, possibly empty, subclass of CGs with no flags itself containing a, possibly empty, subclass of directed acyclic graphs (DAGs). LWF-Markov equivalence classes of CGs can be naturally characterized by means of the so-called largest CGs , whereas a graphical characterization of equivalence classes of DAGs is provided by the essential graphs . In this paper, we show the existence of largest CGs with no flags that provide a natural characterization of equivalence classes of CGs of this kind, with respect to both the LWF- and the AMP-Markov properties. We propose a procedure for the construction of the largest CGs, the largest CGs with no flags and the essential graphs, thereby providing a unified approach to the problem. As by-products we obtain a characterization of graphs that are largest CGs with no flags and an alternative characterization of graphs which are largest CGs. Furthermore, a known characterization of the essential graphs is shown to be a special case of our more general framework. The three graphical characterizations have a common structure: they use two versions of a locally verifiable graphical rule. Moreover, in case of DAGs, an immediate comparison of three characterizing graphs is possible.  相似文献   
47.
In 2001, Swedish authorities imposed a new obligation upon all firms with ten or more employees to undertake annual wage surveys, ‘workplace equality audits’ in which it is possible to ascertain, remedy and prevent unwarranted wage differentials and other unfair employment terms between men and women. An important implication of the new system, called ‘workplace equality renewal’ (självsanering), is that, at the level of the firm all Swedish employers must explain what they mean by work of ‘equal value’ as opposed to ‘different value’. This article discusses the practical pros and cons of the new system, and considers how the surveys can be used in research into the present state of gendered work division. A main finding is that the introduction of this new legislation in the long run might change the Swedish industrial relations system as well as the preconditions for many companies’ human resource management policies. Yet, neither the governmental agencies involved nor the parties’ confederate organizations have been able to clarify what the issue is really about to the single, small business employer or to the local trade union branches. Many employers find any interference, whatever it may be, threatening and trade unions have not realized the potentialities of the system from an employee perspective, potentialities connected to the fact that companies are now more or less forced to make transparent their wage policies at large.  相似文献   
48.
对于江苏来说,国际制造业基地目标意味着在10年内制造业国内生产总值将增长2.3倍。如何实现这一极具挑战性的战略目标呢?大力发展制造业产业集群是一个可行的途径。产业集群具有独特的竞争合作机制,能促使成员企业在规模不变的情况下形成高度专业化分工,实现外部规模经济和对资源的充分利用,从而提升整个产业的竞争力。将资源禀赋、产业基础、产业发展空间、地理区位、承接国际制造业转移等因素综合起来考虑,江苏省应当重点发展信息、石化、医药、纺织、装备、汽车及关键零部件等6大制造业集群。  相似文献   
49.
在一个简单的二级供应链系统中,建立了供应商和零售商同时具有风险规避和公平偏好的收益共享契约协调模型,通过修正、扩展FS效用收益模型,先后考察并分析了分散决策和集中决策下供应链的协调状态,研究发现,供应商和零售商的风险规避系数和公平偏好系数及收益份额必须满足特定的条件,收益共享契约才能使系统供应链整体达到协调状态;在此基础上,对风险规避和公平偏好因素进行敏感度分析,得到供应商和零售商行为偏好系数对供应链及成员最优订货量的影响;最后进行演化博弈算例分析和结论验证,体现了该协调模型的有效性和实用性。由此说明供应商和零售商的风险规避和公平偏好因素同时作用会改变系统供应链协调时的最优订货量,并对决策人的决策行为产生很大的影响。  相似文献   
50.
本文以2009—2018年间中央及地方(以北京市等四个地区为例)颁布的263项新能源汽车产业政策为研究样本,从实施领域角度,将产业政策分为财税支持、行业规范、规划引导、监督保障、其他措施等五类,经政策分解,将政策片段与新能源汽车产业链五个环节进行匹配;在此基础上,测度不同时期产业政策央地总体协同度与政策实施领域间的协同度,并通过逐步回归法,确定影响政策协同的各政策效力指标灵敏度。研究表明:"中央-北京"和"中央-深圳"的政策措施协同趋势基本一致,产业价值链各环节发展较均衡,而"中央-上海"和"中央-江苏"的政策措施协同趋势基本一致,存在"重使用、轻研发、轻市场"等失调现象;四地区与中央政策措施的协同差异主要体现在研发、生产和回收环节,提升"政策引导"和"保障措施"指标的政策效力有助于提升央地协同水平。根据政策分析,未来政策制定需从优化中央政策推广方式和加强监管保障等政策措施着手,根据产业链不同环节状况适时调整政策措施。  相似文献   
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