Panel LM unit root tests with level and trend shifts

This paper considers a Lagrange multiplier (LM) based panel unit root test that allows for heterogeneous structural breaks in both the intercepts and slopes of a series. We note that many popular time series variables are likely to exhibit changing means and/or trends over time. Given that the usual tests will depend on the nuisance parameters indicating the locations of the trend breaks, we adopt a transformation procedure that makes our new panel unit root tests invariant to the nuisance parameters. To illustrate the importance of the power gain provided by our test, we examine the convergence hypothesis using relative ratios of per capita health care expenditures in 20 OECD countries. Our results provide evidence that the convergence hypothesis is supported.     

国家科技创新能力时空差异性评价

科技创新规模扩张和科技创新效率提升是增强国家科技创新能力的两条关键途径。基于现有研究鲜有结合科技创新规模和科技创新效率开展国家科技创新能力评价的现状，采用因子分析法，系统筛选国家科技创新规模影响因素，并结合科技创新效率影响因素，完善国家科技创新能力评价指标体系，通过构建DEA Malmquist指数模型，评价不同时期国家科技创新效率变化指数，以及中国与全球10个国家科技创新能力的时空差异性。研究表明，R&D投入强度、R&D研究人员、专利申请量、科技期刊文章数、高科技产品出口额占制成品出口总额的百分比、科技创新效率是影响国家科技创新能力的关键指标；1991-2014年中国科技创新能力水平呈指数增长态势，有力提升了国家科技实力；全球10个国家科技创新能力水平除日本出现一定波动外，其余九国整体呈小幅递增态势。     

我国商品流通的变迁与发展趋势

计划体制下形成的是与高度集权的经济体制相适应的分配式商品流通组织体系。转轨时期商品流通呈现“三多一少”的格局，流通的低层次性和非系统化。未来的商品流通呈现出弱化二元经济特征、批发业革新、信息化等趋势。     

数字时代的银行业变迁——网点布局与行业结构

数字技术可以帮助市场主体重构组织模式,数字经济时代的金融业也因此迎来变革。本文基于2014年至2019年我国县级行政区数据,研究发现,数字金融的发展显著减缓了我国银行业金融机构实体网点的扩张势头,这种效应主要体现在股份制商业银行和城市商业银行上,并主要影响这两类银行的基层机构。同时,我们发现数字金融的发展加快了农村合作金融机构的转型和网点退出,但对国有“六大行”没有显著影响。进一步研究发现,数字金融的影响效果会随着经济发展程度提高和地区金融可得性增加而增强,但随着在位银行的市场势力提升而下降。本文为理解数字经济时代银行业的变迁提供了一定参考。     

Evaluation of the social and economic impact of carbon dioxide (CO2) emissions on sustainable mobility using cumulative ordinal models: trend odds model

In the context of environmental sustainability evaluation, grouped under climate change, health and ecosystem themes, an impact that could be investigated is the Global Warming Potential (GWP), whose sources are a multitude. In urban areas the evaluation of real vehicles emissions is an essential activity in order to suggest possible solution to local administrators. They still express the need to improve and maintain the characteristics of the breathing air at the best possible quality level. Moreover, these solutions, such as planning measures or traffic control management in respect of pollution, would be apply at different geographical levels, i.e. national, regional or urban scale. Another factor to be investigated is the effect of technologies and emission control systems to comply more stringent limits (Euro 4/5/6) and improve air quality to a lower environmental impact. GWP, indicator of climate change, is measured in terms of CO₂ equivalency emission values variable. To perform this activity an experimental campaign was carried out with several vehicles from different manufacturers and with a wide variety in terms of mass, power, engine displacement and type approval technology. The experimental plan includes some repetitions of the urban section in Naples city centre.The purpose of this paper is twofold: first, to provide a strategy on the choice of a logistic model with ordinal data and with trend, and, second, to evaluate the usefulness of such models for environmental sustainability (CO₂ and other vehicular pollutant emissions), with particular emphasis on model formulation, the interpretation of model coefficients, and the implications of such models.     

Evolutionary social science and universal Darwinism

How should social scientists, inclined to an evolutionary theory of aspects of human culture like science, technology, business organization and practice, react to proposals that they embrace a “Universal Darwinism”? The most prominent variety of Universal Darwinism argues for close counterparts between the variables and mechanisms of cultural evolution and biological evolution, for example proposing the concept of “memes” as units of culture. Other Universal Darwinists propose, more flexibly, that human culture and biological species both change over time through a process that involves variation and selection, but that the details of the processes may be very different. This essay argues that the narrower form of Universal Darwinism should not be acceptable to social scientists. The differences in the details of cultural evolution and biological evolution are considerable. On the other hand, if Universal Darwinism provides a roomy intellectual tent welcoming scholars studying a variety of topics, with the unifying element being a dynamic theory involving variation and selection, but with the key variables and mechanisms being recognized as perhaps differing greatly between biology and human culture, we can be happy in that camp. Evolutionary Social Science and Universal Darwinism.     

When is it coevolution?

This paper evaluates the differences between Norgaard's and Winder et al.'s approach to socio-environmental coevolution. Winder et al. emphasize the evolutionary dynamics of coevolutionary change. These were omnipresent in Norgaard's work but they have not been adequately explored by other ecological economists. I argue that Winder et al.'s definition of coevolution is in essence the same as Norgaard's and that their real differences are, how they see coevolution applied and how far they are willing to draw a priori a line between evolutionary and non-evolutionary socio-environmental dynamics. My thesis is that at this stage a more open approach to evolutionary dynamics and coevolution a la Norgaard is a wiser strategy than Winder et al.'s narrower approach.     

Evolutionary foundations of aggregate-taking behavior

Summary. I show that aggregate-taking behavior is often evolutionarily stable for finite population in symmetric games in which payoff depends only on own strategy and an aggregate. I provide economic examples exhibiting this phenomenon. Received: August 27, 2001; revised version: January 29, 2002 RID="*" ID="*" The paper has profited from the comments of Maria Montero, Burkhard Hehenkamp, Wolfgang Leininger, and Dave Furth. Financial support from the DFG via Postgraduate Programme at the University of Dortmund and via SFB 504 at the University of Mannheim is acknowledged. RID="*" ID="*" Present address: University of Mannheim, SFB 504, L 13, 15, 68131 Mannheim, Germany (e-mail: possajen@sfb504.uni-mannheim.de)     

产出吸引、制度演进与增量改革的产权边界——基于中国制度演进路径的动态考察

制度演进理论将制度变迁行为归结为制度主体对环境的学习和适应过程,在完全信息和缺乏外在约束条件下,制度将会按照某种方式向最优的均衡路径逼近。但是,信息的不完全性、经济实体的制度兼容性以及转轨经济面临的产权、效率约束都会改变制度演进的路径和结果。根据Barro(1991)和Skott(1999)的分析框架,通过构建制度的动态演进方程,文章对在一定约束条件下的制度演进长期均衡路径进行了考察,勾勒出一幅全新的制度演进图景。同时,运用相关的宏观经济数据,文章考察了模型对中国经济制度演进路径的解释能力。     

带有结构突变的单位根检验——文献综述

单位根检验是时间序列分析的基础,而是否考虑结构突变对单位根检验的结论有着重要影响,因此,考虑结构突变的单位根检验已成为计量经济学界的一个前沿热点问题。本文回顾了这一问题的发展历史,总结了该领域已取得的一些重要研究成果,最后对该问题最新的发展动向加以概括。