我国上市公司再融资与财务业绩动态变化研究

本文对上市公司再融资的3种形式及对财务业绩在时间上的变化进行了分析，提出了无论配股、增发新股、发行可转换债3种方式对财务指标的影响是下滑的，而对企业的核心业务是增强的，但不显著。发行可转债优于配股和增发。     

旅游地文化空间及其演化机理

旅游活动的文化属性决定了旅游地本质上是为旅游者提供一个文化空间。从旅游地文化的空间研究转向空间的文化研究,并厘清旅游地文化空间的内涵及其演化机理,寻求旅游地的文化发展规律,有助于解决旅游规划与开发中"造文化、造景观"的困境。基于空间生产和景观生态学原理,以及旅游地文化空间的活态性,旅游地文化空间的时间和功能演化是由原居民的生产与生活空间演变为服务于旅游发展的生产与生活空间的过程。旅游地文化空间在形态上,则表现为文化节点、文化轴线、文化场、文化域面等基本空间形态的形成与演化。文化场作为最为重要的空间形态,它是旅游地进行生产、生活与服务的真实场景,体现了人与旅游景观的社会文化关系。     

金融风险度量方法的新进展

本文对风险度量的新进展进行了讨论,介绍了一些当前流行的风险度量工具,并从失真函数的角度考察风险度量,指出它们和传统方法的区别,同时对动态风险度量方法也进行了总结。     

A general endogenous grid method for multi-dimensional models with non-convexities and constraints

The endogenous grid method (EGM) significantly speeds up the solution of stochastic dynamic programming problems by simplifying or completely eliminating root-finding. We propose a general and parsimonious EGM extended to handle (1) multiple continuous states and choices, (2) multiple occasionally binding constraints, and (3) non-convexities such as discrete choices. Our method enjoys the speed gains of the original one-dimensional EGM, while avoiding expensive interpolation on multi-dimensional irregular endogenous grids. We explicitly define a broad class of models for which our solution method is applicable, and illustrate its speed and accuracy using a consumption–saving model with both liquid assets and illiquid pension assets and a discrete retirement choice.     

The optimal portfolio for the two-pillar mandatory pension system: the case of Poland

In the recent decade, there has been observed across the Central and Eastern European states the regulatory trend towards the increase of the non-financial (first) pension pillar size at the expense of the financial (second) pillar. It tends to question the consequences of this shift for the future retirement benefits. Applying the portfolio approach we address this issue by running a series of simulations to find out how to allocate pension contributions between both pillars in an optimal way. Our study contributes to the existing literature as follows. First, we do not perform the assessment of the predetermined regulatory solutions, but we look for an optimal one. Moreover, we allow our optimal rule to be time-varying, if necessary, which would be a true novelty in this research area. Second, we do not base our estimates on historical trends; rather, we apply the long-term economy’s projection to account for the society’s ageing impact, which is a crucially important factor for the solvency of the pension system. Adapting some of the simulation assumptions to fit the Polish case, our results confirm that current regulations underestimate the role of the capital pillar and the optimal allocation between both pillars should be time-varying.     

Learning by doing,spillovers and shakeouts

This paper studies industry evolution driven by non strategic learning by doing and spillovers. We characterize a dynamic process of cost and output changes and its effect on welfare and industry profits. The paper gives conditions for shakeouts to occur and analyzes the key factors affecting these conditions. Since shakeouts could lead to a long-run social loss due to higher market concentration, there is a role for a government to play in limiting unnecessary shakeouts. The most effective way to do so is to enhance spillovers.JEL Classification: L11, L13, O31Correspondence to: Michael TroegeWe would like to thank Hans Mewis, Christophe Moussu and an anonymous referee for valuable comments and suggestions. We also benefited from comments of seminar participants at WZB, Humboldt University, Northwestern University and the EEA/ESEM 1999 meetings. Part of the research was carried out while Michael Tröge was visiting Northwestern University. Financial support by the German Research Council (DFG) is gratefully acknowledged.     

山西省科技发展能力分析——基于系统动力学

以山西省科技发展能力为研究对象,使用Vensim PLE软件建立了科技发展能力的系统动力学模型,并对山西科技发展能力进行了仿真、预测和政策模拟,明确了影响山西省科技发展能力的两个重要因素——R&D经费投入占GDP的比例和科技人员数。最后提出政策建议。     

基于遥感与GIS的区域土地利用变化的动态监测与预测研究

本文以广西苍梧县沙头、石桥两镇为例,利用航空遥感调查方法结合GIS技术,定量分析研究区域内土地利用动态变化过程,以及土地利用各类型之间的相互转化状况.运用马尔柯夫原理,建立齐次马尔柯夫链模型中的转移概率矩阵,对研究区未来土地利用演变趋势进行模拟与预测.     

洞庭湖区旅游城镇化的时空分异及演化

从旅游产业、城镇化和生态环境3个维度构建旅游城镇化指标体系,运用状态空间法,分析2000—2018年洞庭湖区17个县域旅游城镇化的时空分异及其演化机理。结果表明:①2000年以来洞庭湖区旅游产业指数呈现上升趋势,但是整体水平偏低;城镇化指数呈现明显快速上升态势,整体水平较高;生态环境指数大致呈"W"型变化趋势,且整体水平偏低;旅游城镇化指数不高,均值为0.3737,大致经历了3个变化阶段,基本上与城镇化指数变化一致。②城镇化指数>旅游产业指数>生态环境指数,说明旅游城镇化的发展同城镇化和旅游产业子系统具有高度协同性,与生态环境子系统具有反向性,反映出城镇化和旅游产业的快速发展给生态环境产生了强大压力,一定程度上制约了旅游城镇化指数的整体提升。③近20年来洞庭湖区旅游城镇化发展的空间差异明显,旅游产业指数和城镇化指数的空间分布格局表现为湖区中部县域较低,外围县域相对较高,基本上形成以岳阳市区、常德市区和益阳市区3个县域为中心的环带状分布。生态环境指数的地域分布格局表现为湖区中部县域明显高于外围县域,基本上形成以沅江市和南县2个县域为中心的环带状分布。旅游城镇化指数的空间分布格...     

开发区与企业动态成长机制*--基于企业进入、退出和增长的研究

开发区的高速增长到底是源自寻求“政策租”所导致的短期“虚假繁荣”,还是通过集聚效应推动企业迅速成长而形成的长期表现？回答好这一问题,对于开发区政策的效果评价和进一步完善至关重要。然而,现有研究对此却语焉不详。文章在识别开发区企业的基础上,实证检验了开发区对企业进入、退出和成长的作用,以及开发区增长效应的可持续性,揭示了开发区影响地区经济增长的微观机制。研究发现：(1)开发区会吸引高效率企业进入,并降低开发区内企业的退出风险,从而使得开发区内净进入企业数目显著增加,这意味着开发区政策是吸引企业入驻并加强集聚经济的重要因素;(2)开发区显著提高了企业的就业增长、生产率增长和销售增长,这表明开发区政策和集聚经济的增长效应十分明显;(3)企业“入驻”开发区初期,“政策租”带来了短期的快速增长,而开发区内自我加强的集聚经济对企业成长具有长期的促进作用,这说明开发区的增长效应具有可持续性。文章肯定了开发区实践对企业动态成长的长期积极影响,这不仅为开发区政策绩效的评估提供了更为全面的认识,而且也为开发区的进一步发展和完善提供了重要启示。