Uncertain Climate Change in an Intergenerational Planning Model

A three-generation planning model incorporating uncertain climate change is developed. Each generation features a production activity based on capital and an exhaustible resource. An irreversible climate change may occur in period two or three, reducing the productivity for this and the remaining generation. The model is solved by stochastic dynamic programming. If the climate impact and climate change probability is constant, the optimal period one (and two) resource extraction is larger than for the reference case of climate stability. If, however, climate impact and climate change probability increases with increased aggregate resource use, this result is reversed.     

河西地区农牧地域分异与农牧耦合探讨

农牧耦合存在两种基本耦合类型:一是特定地域农(牧)生态系统中农牧业生产之间的内部耦合;二是不同地域农(牧)生态系统之间的农牧空间耦合。在对河西地区农牧空间耦合的自然环境、历史发展、现状结构和问题分析基础上,结合对农牧空间耦合的理论探讨,提出了河西地区农牧空间耦合的发展对策。     

城市生态学视野下的动态适度人口规模——兼论上海人口发展的基本态势

提出城市适度人口规模不是一个静态的数值,而是动态的过程。不是一个先验的数值,而是系统决定的综合结果。建立了一个适度人口规模的概念性框架,即EFL模型,就是说合理和适度的人口规模是与之相联系的资源环境因素、功能和经济方式、空间区位状态共同决定的结果。生态系统的变动,综合决定了一定时期、一定标准下的城市人口适度规模,并决定了这一适度规模的变化趋势。基于这一思路,讨论了影响上海人口规模变动的积极因素和阻碍因素,从资源环境变化、城市功能变化和城市空间变化三个方面对上海适度人口规模的变动趋势作了基本判断,提出上海人口规模将出现先上升再下降的趋势。根据动态适度人口规模的观点,对城市人口综合调控和城市管理的有关问题提出了一些建议。     

产业结构软化及其对世界经济发展的影响

产业结构的状态总是随着经济发展的变化而处于不断变动之中。20世纪中期以来，以信息技术革命为核心的新技术革命的兴起加速了世界产业结构的全方位变革，出现了产业结构软化的趋势。产业结构软化趋势主要表现为产业结构服务化、高技术化、融合化和国际化，它是世界经济发展的必然结果，同时又对世界经济发展产生了重要的影响。     

中国城市化与生态环境耦合规律与实证分析

本文在阐明城市化与生态环境交互耦合含义的基础上,利用城市化的S型生长曲线和生态环境演变的倒U型曲线,演绎出城市化与生态环境耦合的规律曲线,并以中国的实际数据为例,进行实证分析。研究表明:(1)生态环境随城市化发展呈现出着先恶化、后改善的不规则倒U型耦合规律,但该规律曲线只是它们实际耦合的一种演变趋势;(2)1985～2005年间,中国工业废水排放量与城市化水平耦合表现出先倒U型和后U型的阶段特征,而这种特征曲线正是技术进步、产业结构高级化、人们环保意识的增强以及经济增长的压力等因素综合作用的结果。     

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。     

Experimental Economics and the Theory of Decision Making Under Risk and Uncertainty

Following a brief review of the main experimental work into the economics of risk and uncertainty, both static and dynamic, this paper reports the results of an experiment testing one of the key assumptions of the theory of dynamic economic behaviour—that people have a plan and implement it. Using a unique design which enables the plan (if one exists) to be revealed by the first move, the experiment was implemented via the Internet on a subset of the University of Tilburg's ongoing family expenditure survey panel. The advantages of using such a set of subjects for the experiment are twofold: the demographic characteristics of the set are known and therefore demographic inferences can be made; the representativeness of the set is known and therefore inferences about populations can be made. The results suggest that at least 36% of the subjects had behaviour inconsistent with the hypothesis under test: that people formulate plans and then implement them. Interestingly demographic variables are unable to explain the consistency or inconsistency of individuals. One conclusion is that subjects simply make errors. An alternative conclusion, consistent with previous experimental research, is that people are unable to predict their own future decisions. The implications for dynamic theory (particularly relating to savings and pensions decisions) are important.     

The Global Determinants of Direct Office Real Estate Returns

We investigate the determinants of direct office real estate returns by analyzing rents, capital appraisals, and total returns. A recently compiled global database of major cities in Asia, Europe, and the United States provides a unique opportunity to give a macro-view on the effects of economic growth and supply and demand factors on nominal real estate returns. The global database provides quarterly observations from 1986 to 1999. To address the smoothness problem of appraisal-based price data and regulated rents, we employ the Generalized Method of Moments to estimate a dynamic panel-data model. The model allows us to combine the cross-sectional and time-series dimension in our quarterly data. We find that gross domestic product, inflation, unemployment, vacancy rate, and the available stock all have an effect on real estate returns.     

建设工程信息集成管理系统研究

工程项目建设与管理过程中会产生大量的物化的材料——建设工程信息。静态信息资料组卷归档后将成为建设工程项目的档案资料，为工程检查验收及日后的改建、扩建、维修、管理等方面提供极其重要的依据，动态信息则为工程建设过程的管理与决策提供强力支持，而这一切都建立在对建设工程信息的有效管理基础上，从了解建设工程信息特点入手,分析客户的需求，构筑管理系统构架,开发了相应的功能模块，并付诸了实施。     

Export Sophistication: A Dynamic Panel Data Approach

In this article, we analyze export sophistication based on a large panel dataset (2001–2015; 101 countries) and using various estimation algorithms. Using Monte Carlo simulations, we evaluate the bias properties of estimators and show that GMM-type estimators outperform instrumental-variable and fixed-effects estimators. Based on our analysis we document that GDP per capita and the size of the economy exhibit significant and positive effects on export sophistication; weak institutional quality exhibits negative effect. We also show that export sophistication is path-dependent and stable even during a major economic crisis, which is especially important for emerging and developing economies.