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1.
资本创造模型(CC模型)忽视了要素流动对产业空间分布的影响。而发展的新的资本创造模型则认为资本集聚的过程必然伴随着工业劳动力的流动过程。另外,是资本的实际收益而不是名义收益决定资本是否创造。研究结果表明,随着贸易自由度、工业品支出份额及资本贴现率的变大,替代弹性及资本折旧率的变小,将降低对称结构的稳定性,而提高中心-外围结构的稳定性;经济地理空间的产业均衡是集聚力和分散力相互作用的结果。当企业生产工业品的规模报酬递增程度足够显著,或者工业品支出份额很高时,市场拥挤效应将彻底消失,并转化成为促进产业集聚的动力;突破点与持续点的大小比较可以形成不同的关系,这意味着随着贸易自由度的变化,本文发展的资本创造模型可以体现出多样化的产业空间动态演化行为。  相似文献   
2.
Recently, Kambo and his co-researchers (2012) proposed a method of approximation for evaluating the one-dimensional renewal function based on the first three moments. Their method is simple and elegant, which gives exact values for well-known distributions. In this article, we propose an analogous method for the evaluation of bivariate renewal function based on the first two moments of the variables and their joint moment. The proposed method yields exact results for certain widely used bivariate distributions like bivariate exponential distribution, bivariate Weibull distributions, and bivariate Pareto distributions. An illustrative example in the form of a two-dimensional warranty problem is considered and comparisons of our method are made with the results of other models.  相似文献   
3.
In this paper, we consider the deterministic trend model where the error process is allowed to be weakly or strongly correlated and subject to non‐stationary volatility. Extant estimators of the trend coefficient are analysed. We find that under heteroskedasticity, the Cochrane–Orcutt‐type estimator (with some initial condition) could be less efficient than Ordinary Least Squares (OLS) when the process is highly persistent, whereas it is asymptotically equivalent to OLS when the process is less persistent. An efficient non‐parametrically weighted Cochrane–Orcutt‐type estimator is then proposed. The efficiency is uniform over weak or strong serial correlation and non‐stationary volatility of unknown form. The feasible estimator relies on non‐parametric estimation of the volatility function, and the asymptotic theory is provided. We use the data‐dependent smoothing bandwidth that can automatically adjust for the strength of non‐stationarity in volatilities. The implementation does not require pretesting persistence of the process or specification of non‐stationary volatility. Finite‐sample evaluation via simulations and an empirical application demonstrates the good performance of proposed estimators.  相似文献   
4.
A conformance proportion is an important and useful index to assess industrial quality improvement. Statistical confidence limits for a conformance proportion are usually required not only to perform statistical significance tests, but also to provide useful information for determining practical significance. In this article, we propose approaches for constructing statistical confidence limits for a conformance proportion of multiple quality characteristics. Under the assumption that the variables of interest are distributed with a multivariate normal distribution, we develop an approach based on the concept of a fiducial generalized pivotal quantity (FGPQ). Without any distribution assumption on the variables, we apply some confidence interval construction methods for the conformance proportion by treating it as the probability of a success in a binomial distribution. The performance of the proposed methods is evaluated through detailed simulation studies. The results reveal that the simulated coverage probability (cp) for the FGPQ-based method is generally larger than the claimed value. On the other hand, one of the binomial distribution-based methods, that is, the standard method suggested in classical textbooks, appears to have smaller simulated cps than the nominal level. Two alternatives to the standard method are found to maintain their simulated cps sufficiently close to the claimed level, and hence their performances are judged to be satisfactory. In addition, three examples are given to illustrate the application of the proposed methods.  相似文献   
5.
A large literature demonstrates the direct and indirect influence of health on socioeconomic attainment, and reveals the ways in which health and socioeconomic background simultaneously and dynamically affect opportunities for attainment and mobility. Despite an increasing understanding of the effects of health on social processes, research to date remains limited in its conceptualization and measurement of the temporal dimensions of health, especially in the presence of socioeconomic circumstances that covary with health over time. Guided by life course theory, we use data from the British National Child Development Study, an ongoing panel study of a cohort born in 1958, to examine the association between lifetime health trajectories and socioeconomic attainment in middle age. We apply finite mixture modeling to identify distinct trajectories of health that simultaneously account for timing, duration and stability. Moreover, we employ propensity score weighting models to account for the presence of time-varying socioeconomic factors in estimating the impact of health trajectories. We find that, when poor health is limited to the childhood years, the disadvantage in socioeconomic attainment relative to being continuously healthy is either insignificant or largely explained by time-varying socioeconomic confounders. The socioeconomic impact of continuously deteriorating health over the life course is more persistent, however. Our results suggest that accounting for the timing, duration and stability of poor health throughout both childhood and adulthood is important for understanding how health works to produce social stratification. In addition, the findings highlight the importance of distinguishing between confounding and mediating effects of time-varying socioeconomic circumstances.  相似文献   
6.
科技企业是实现科技创新的驱动者和科技成果转化的重要载体,也是推动研究开发的重要参与者,科学评价科技企业创新能力有助于企业自身不断发展壮大。在分析国内外新区科技企业创新驱动发展相关理论研究的基础上,从研发投入、研发基础、研发效益和现代科技四个角度,运用层次分析法构建科技企业创新能力评价系统,并通过实证分析说明评价系统的可靠性;根据评价系统测算出现阶段雄安新区科技企业创新能力,通过与成熟新区科技企业的比较,发现其短板和不足,力图为决策者科学合理评价、管理科技企业创新发展提供有益参考。  相似文献   
7.
Modeling spatial overdispersion requires point process models with finite‐dimensional distributions that are overdisperse relative to the Poisson distribution. Fitting such models usually heavily relies on the properties of stationarity, ergodicity, and orderliness. In addition, although processes based on negative binomial finite‐dimensional distributions have been widely considered, they typically fail to simultaneously satisfy the three required properties for fitting. Indeed, it has been conjectured by Diggle and Milne that no negative binomial model can satisfy all three properties. In light of this, we change perspective and construct a new process based on a different overdisperse count model, namely, the generalized Waring (GW) distribution. While comparably tractable and flexible to negative binomial processes, the GW process is shown to possess all required properties and additionally span the negative binomial and Poisson processes as limiting cases. In this sense, the GW process provides an approximate resolution to the conundrum highlighted by Diggle and Milne.  相似文献   
8.
英国自都铎王朝后期至斯图亚特早期,立宪君主论或混合君主论者抵制君权神授论,坚持家庭是一个自治的、涉及臣民私人权益的小政府,受到自然法、古代宪法或神圣法的保护。《复仇者悲剧》中公爵王室言行映射詹姆士一世在《皇家礼物》中所宣扬的君权神授论,温迪斯兄弟俩及追随者的复仇隐含当时的政治抵制学说,公爵王室与温迪斯兄弟俩的对立象征君权神授论与普通法理论的对峙。温迪斯兄弟俩却以威胁新君为由被处死,司法斗争简约为复仇冲动,维权英雄陡变为暴徒,暴君化身为明君,这暴露出君权神授论的悖论性和剧作家含混的复仇伦理。  相似文献   
9.
《1844年经济学哲学手稿》和《神圣家族》都是马克思主义创始人早期思想的代表性著作,二者都把“生活”作为重要概念进行论述。从作为经济学哲学概念到作为社会批判概念,马克思主义创始人对“生活”的认识经历了从对物质生产活动的重视到对无产阶级普遍贫困生活的揭露,从分析“生产生活”的异化到对“非人性”生活的批判,从“生活的手段”到消灭“非人性的生活条件”的思想历程。人类的历史是人类生活发展的历史。解决人的美好生活如何实现的问题,在马克思恩格斯的生活思想中居于核心地位,这对当今中国具有重要的理论指导价值。中国特色社会主义进入新时代,从开启一种全新文明的生活形态的高度来理解新时代的美好生活,才能准确把握我国社会主要矛盾变化的深刻意义。  相似文献   
10.
英国作家哈代受古希腊悲剧的影响是明显的,对其小说《卡斯特桥市长》的分析可为此提供个案视角。从小说主人公亨察尔与古希腊神话人物俄狄浦斯的故事模式的比对,可以看出哈代对古希腊命运悲剧遗绪的继承,可以看出主人公亨察尔的悲剧既是性格悲剧,也是命运悲剧;通过对亨察尔这一形象的重新解读,可以从四种原型模式来观照《卡斯特桥市长》。  相似文献   
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