日韩东盟8国入境我国旅游与进出口贸易关系的研究

国际旅游与国际贸易是相互联系的,旅游引发贸易、贸易推动旅游。本文在前期研究工作的基础上,提出了一个旅游与贸易互动的三阶段模型,即旅游引发贸易、贸易推动旅游和偏好-容量限制3个阶段。以日韩东盟8国为例,选用1986年-2009年统计数据,分析了8国入境我国旅游与进出口贸易的关系,构建了入境客流量与进口贸易、出口贸易和进出口贸易3组24个推拉方程。在此基础上,以1992年和2002年为分界点,分析了各阶段入境客流量与进口贸易、出口贸易增长率的变化及弧弹性;依据每万人次入境旅游引发的进出口贸易强度,将日韩东盟8国划分为四种类型,分析了近10年来旅游引起进出口贸易强度的变化,为通过旅游拉动贸易或通过贸易推动入境旅游发展提供了科学依据。     

上海大都市区物联网产业集聚与空间演化

新兴技术产业的空间集聚与扩散对大都市区的空间结构有直接的影响,厘清新兴技术产业的空间分布和区位选择规律对新兴产业集群培育和大都市区空间结构调整都具有重要的政策意义。本文分析了上海市物联网企业的空间分布和集聚特征,结果发现初创期物联网企业在郊区集聚,随后向郊区其他区域扩散,并呈现出从单极向多极集聚转变的空间演化进程。通过构建负二项回归探究上海物联网企业的区位选择因素,结果表明制度因素和企业集聚效应对企业区位选择有重要影响。在产业发展初创期,企业区位选择受政府管制和市场机制双重影响,其中制度因素发挥了关键作用;而在随后的兴起期,产业集聚效应对新企业的入驻具有强大的吸引力。     

北京城市空间认知的影响因素分析

城市空间认知影响因素分析与认知空间格局研究具有同等的重要性。论文基于北京城市空间认知调查问卷数据,引入居民属性等16个变量,利用二值Logistic回归方法,提炼出23个认知地点整体以及交通节点、商场、休闲地三种类型地点的认知影响因素。发现:第一,不同类型地点的认知率影响因素存在异同,其中,存在职住变更是最为显著的共性因子。第二,各类地点中的显著影响因子对认知率的作用大小有明显差异,年龄46-55岁变量是23地点认知率的最重要影响因素,交通节点和商场认知率最重要的影响因素为就业内城四区,而就业地与休闲地距离小于等于6km变量对休闲地认知率的影响最大。第三,各类模型中的影响因素类型不同且影响程度有很大差异,故具有不同属性信息组合的居民认知率不同。     

陶器古剂量线性回归方法和误差评估

陶器古剂量P包含等效剂量Q和超线性修正I两个部分,为了提高古剂量测量的准确性,正确地计算古剂量的测量误差,本工作测试了10个古陶片样品,利用线性回归方法计算等效剂量Q和超线性修正I,并对不同的古剂量计算方法进行误差分析和评估。研究表明,线性回归方法(包括归平法和平归法)计算陶器古剂量的准确性优于目前采用的常规法;通过几种不同方法的误差比较和分析,归平法所得误差较其它方法更严谨、合理。该研究在提高古剂量测量的准确性和正确计算古剂量的测量误差两方面具有重要的意义,使得古剂量的测量更加合理,符合数理统计规律。     

Deletion/Substitution/Addition (DSA) model selection algorithm applied to the study of archaeological settlement patterning

This paper introduces GIS-based statistical methods for the study of settlement patterning in an archaeological context. The main aspect is an improvement over suboptimal stepwise statistical model selection procedures, with the introduction of a Deletion/Substitution/Addition (DSA) algorithm, a systematic model selection algorithm that provides an optimal model choice. The paper also introduces the combined use of Receiving Operator Characteristic (ROC) curves, and variable ranking as key tools aimed at an understanding of settlement patterning causation. An illustrative case study is provided whereby both a purely environmental and a mixed environmental/historical model (based on settlement hierarchy considerations) are investigated.     

From Fertility Intention to Fertility Behaviour

Using longitudinal data from Jiangsu Fertility Intention and Behaviour Study (JFIBS) from year 2007 and 2010, this study analyses the fertility intention and behaviour of women who are qualified to have two children from a psychosocial point of view. Based on the Theory of Planned Behaviour, the theoretical framework from fertility intention to fertility behaviour is reconstructed. By observing the phenomenon from the micro-level, the gap between female fertility intention and behaviour and its associated factors are studied. The result shows that, given the situation of being qualified to have two children according to the government's birth control policy, when faced with the choice of whether to have a second child or not, people tend to make their decisions rationally. Attitudes towards fertility, subjective norms, and perceived behaviour control all contribute significantly to the discrepancy between fertility intention and behaviour. In addition, the formation of a concrete birth plan is a major driving force for translating fertility intention into action.     

旅游产业集聚会影响地区收入差距吗？——基于中国省际面板数据的门槛回归分析

本文利用中国30个省市区1999年～2009年面板数据,分别从线性和非线性两个角度实证检验了旅游产业集聚对地区收入差距的影响,估计结果显示：一方面,旅游产业集聚对地区收入差距具有显著线性负向影响效应;另一方面,通过构建非线性面板门槛模型,进一步检验了旅游产业集聚对地区收入差距影响效应的门槛特征,具体而言,旅游产业集聚对地区收入差距负向影响效应不仅存在基于旅游产业集聚的单一门槛特征,而且也存在基于经济发展水平、基础设施建设与产业结构升级的三重门槛特征。     

Own-child estimates of U.S. white fertility, 1886–99

Abstract

The collapse of empires is exceedingly difficult to understand. The author examined the distribution of imperial lifetimes using a data set that spans more than three millennia and found that it conforms to a memoryless exponential distribution in which the rate of collapse of an empire is independent of its age. Comparing this distribution to similar lifetime distributions of other complex systems—specifically, biological species and corporate firms—the author explores the reasons behind their lifetime distributions and how this approach can yield insights into empires.     

Wasserstoff als Energieträger. Herstellung,Lagerung, Transport

Abstract

This essay, written to accompany a lecture to new students on the course of Economic Analytics, at the Institute of Econometrics of the University of Lodz in Poland, provides a broad historical account of the development of econometrics. The context enables students to locate various aspects of econometric analysis. The origin of regression analysis is described and an account of cointegration analysis is presented. This essay is concerned primarily with the propagation of the ideas as distinct from the manner and the circumstances in which they have originated.     

NOTE ON THE INCLUSION OF SITE CLASSIFICATION INFORMATION IN EQUATIONS TO ESTIMATE STRONG GROUND MOTIONS

Two main regression methods have been proposed for using site category information within ground motion prediction equations, these are: (a) joint estimation of the site category coefficients and the magnitude and distance coefficients; or (b) estimation of site category coefficients by using the residuals from the equation derived without considering soil conditions. Method (a) requires each record be assigned a site category whereas for method (b), because it relies on residuals, site information can be missing for some records. This short note finds that if the mean of the transformed distances within each site category is the same then the two methods give the same site coefficients. If, however, these means are significantly different then method (b) can yield incorrect site coefficients.