空间经济计量滞后模型Bootstrap Moran检验功效的模拟分析

 当误差项不服从独立同分布时,利用Moran’s I统计量的渐近检验,无法有效判断空间经济计量滞后模型2SLS估计残差间存在空间关系与否。本文采用两种基于残差的Bootstrap方法,诊断空间经济计量滞后模型残差中的空间相关关系。大量Monte Carlo模拟结果显示,从功效角度看,无论误差项服从独立同分布与否,与渐近检验相比,Bootstrap Moran检验都具有更好的有限样本性质,能够更有效地进行空间相关性检验。尤其是,在样本量较小和空间衔接密度较高情况下,Bootstrap Moran检验的功效显著大于渐近检验。     

广西北部湾经济区产业布局对转变经济发展方式的影响分析

经济发展方式的转变是北部湾经济区的必然选择。北部湾经济区开发带来了一系列重大工业布局和重点项目建设,对经济增长和产业结构升级带来了明显的效果,但是也产生了一系列的问题。北部湾经济区应从产业布局的角度调整优化投资结构、产业结构等,促进经济区发展方式转变。     

Investigating the sensitivity of Gaussian processes to the choice of their correlation function and prior specifications

A Gaussian process (GP) can be thought of as an infinite collection of random variables with the property that any subset, say of dimension n, of these variables have a multivariate normal distribution of dimension n, mean vector β and covariance matrix Σ [O'Hagan, A., 1994, Kendall's Advanced Theory of Statistics, Vol. 2B, Bayesian Inference (John Wiley & Sons, Inc.)]. The elements of the covariance matrix are routinely specified through the multiplication of a common variance by a correlation function. It is important to use a correlation function that provides a valid covariance matrix (positive definite). Further, it is well known that the smoothness of a GP is directly related to the specification of its correlation function. Also, from a Bayesian point of view, a prior distribution must be assigned to the unknowns of the model. Therefore, when using a GP to model a phenomenon, the researcher faces two challenges: the need of specifying a correlation function and a prior distribution for its parameters. In the literature there are many classes of correlation functions which provide a valid covariance structure. Also, there are many suggestions of prior distributions to be used for the parameters involved in these functions. We aim to investigate how sensitive the GPs are to the (sometimes arbitrary) choices of their correlation functions. For this, we have simulated 25 sets of data each of size 64 over the square [0, 5]×[0, 5] with a specific correlation function and fixed values of the GP's parameters. We then fit different correlation structures to these data, with different prior specifications and check the performance of the adjusted models using different model comparison criteria.     

Spatially correlated Poisson sampling

A new method for sampling from a finite population that is spread in one, two or more dimensions is presented. Weights are used to create strong negative correlations between the inclusion indicators of nearby units. The method can be used to produce unequal probability samples that are well spread over the population in every dimension, without any spatial stratification. Since the method is very general there are numerous possible applications, especially in sampling of natural resources where spatially balanced sampling has proven to be efficient. Two examples show that the method gives better estimates than other commonly used designs.     

中国区域经济协调发展实证研究

 由于我国经济发展的区域不均衡性,区域经济的协调发展问题不仅是我国一项长期重要国策,也使其成为社会经济研究的热点问题。本文将空间计量模型与面板分析方法相结合,以我国省域经济发展作为研究对象和数据来源,从而对我国省域经济增长的协调发展和所受影响因素进行研究。结果显示,我国区域经济发展存在着显著的空间相关性,在经济发展的不同阶段影响经济增长的因素不同,对经济发展有持续显著正影响的因素有：人力资本、人口资本、市场化进程和财政支出等。据此本文提出若干政策建议,以促进我国经济协调增长。     

中国分代家庭户的空间分布特征研究

家庭是社会的基本组成单位,家庭户结构的变化直接影响到社会生活的各个方面,家庭户代际结构的分布则能从直观上认识家庭户结构。本文基于2000年第五次全国人口普查的分代家庭户数据及相关资料,以空间自相关分析为基础,对五普数据中的分代家庭户比例分布进行了初步分析。发现其空间分布特征呈现明显的正相关性。为了进一步研究这种空间分布,采用GIS方法得到分代家庭户比分布图,分析发现：二代户仍然是中国家庭户的主要模式;不同地区分代家庭户的分布呈现明显的差异,北方地区的二代户比例最高;三代户与四代以上户分布特征相似,主要集中在西南地区;分代家雇户的分布与绎济发展水平、宗教信仰和民族风俗密切相关．     

上海市人户分离状况的空间特征分析——基于“六普”数据

＂六普＂数据显示,近几年上海市人户分离状况呈现出新的空间特征,主要表现在：人户分离人口的规模和迁移率在空间分布上呈现出严重的不均衡;大部分区县人户分离人口的来源地及迁居目的地集中化程度高,具有＂近邻优先＂的特点;逐步形成由中心城区县流向近郊区区县和中心城区县之间相互流动的两大迁移圈;中心城核心区、边缘区、近郊区、远郊区等四大区域之间的人户分离人口流动呈现出三大迁居主流。本文在总结这些空间特征的同时,就如何解决上海市人户分离问题提出了几点建议,以期上海市内户籍人口的迁移能科学健康有序进行。     

张拉整体索穹顶结构的预应力优化设计

空间张拉索穹顶整体结构是一类有无穷小机构位移的静不定且动不定结构,需要提供预应力完成几何整体性的构造．本文通过对预应力空间铰接体系的设计分析,提出了包括索和压杆的预应力优化设计方法,此方法是基于矩阵分析的柔性方法,它能够找到预应力和机构的状态且优化受压构件的预应力设计．     

Bayesian analysis of agricultural field experiments

The paper describes Bayesian analysis for agricultural field experiments, a topic that has received very little previous attention, despite a vast frequentist literature. Adoption of the Bayesian paradigm simplifies the interpretation of the results, especially in ranking and selection. Also, complex formulations can be analysed with comparative ease, by using Markov chain Monte Carlo methods. A key ingredient in the approach is the need for spatial representations of the unobserved fertility patterns. This is discussed in detail. Problems caused by outliers and by jumps in fertility are tackled via hierarchical t formulations that may find use in other contexts. The paper includes three analyses of variety trials for yield and one example involving binary data; none is entirely straightforward. Some comparisons with frequentist analyses are made.     

浙江县域经济融入都市圈发展研究:方法与实证

都市圈崛起是区域发展的显著现象,并且对区域发展产生重要而深远的影响.县域经济融入都市圈发展是必然趋势.本文在回顾都市圈发展及其理论研究、界定方法的基础上,运用修正的引力模型对浙江空间发展的大格局、县域在都市圈发展中的定位、都市圈的边界确定等进行了实证分析,提出要根据各县域不同的条件特点,分门别类地予以制度激励和政策指导,促进县域经济融入都市圈发展.