中国城市化和经济增长关系的计量分析

传统观点认为经济增长带动城市化的发展,城市化对经济增长的促进作用很有限.本文通过运用格兰杰因果检验、状态空间模型和向量自回归模型对城市化和经济增长的关系进行实证研究发现.与传统的观点相反,城市化对经济增长具有很大的促进作用,相反经济增长对城市化的影响是很有限的.城市化促进区域经济增长,主要是通过扩大内需而实现的,也就是城市化促进区域经济增长机制是内需的扩大.本文根据实证研究结果,也进行了加快我国城市化的相关措施的讨论.     

中国经济快速发展中的集聚经济转型研究

从经验角度看,伴随我国各区域经济快速增长,城市化经济和地方化经济的发展如火如荼.在理论界,城市化经济和地方化经济对促进经济增长作用的探讨一直没有停息.对这一问题的深入研究有助于我们理解不同发展阶段的城市对地方集聚经济发展模式的需求,便于我们更好的制定产业政策,发展地方产业.文本利用1978年至2001年面板数据研究中国长期经济增长中的主要作用要素,发现城市化经济指数与经济增长的弹性系数最大,是促进各区域经济发展的主导因素.为了进一步探究城市化经济和地方化经济在经济增长中发挥的作用及其变动过程,作者又选取了1997年和2003年30个省区的24个工业企业数据进行横截面研究,通过跨年度研究的结果比较,发现城市化经济在不同的行业,正在逐渐替代地方化经济成为促进增长的主要因素.     

制造业结构变动和生产率增长——基于不同影响机制的实证研究

结构变动是生产率增长的重要源泉。本文将结构变动对劳动生产率增长的影响分为直接作用和间接作用。前者通过生产率快速增长的行业扩大比重实现;后者通过"与用户相关的外溢"等机制实现。对我国1980-2010年制造业内部结构变动对劳动生产率增长的研究发现:单纯从直接作用看,我国制造业内部结构变动对生产率提高的作用并不明显;而进一步利用动态面板衡量直接作用和间接作用的总和,发现制造业结构变动明显影响生产率的变动。这也说明我国制造业结构变动主要是通过间接方式影响劳动生产率提高。     

中国区域经济增长与FDI的区域差异分析

改革开放以来,外商直接投资(FDI)不断涌入我国,并对我国经济增长和制度变迁发挥了重要的推动作用。然而,外资并没有均衡地进入到我国各地区。从东、中、西三大地带看,东部地区占据绝对优势,外资的区域分布差异异常悬殊。FDI在地理空间上的这种非均衡分布及其变动趋势对中国区域经济的平衡发展和持续增长产生了深远的影响。     

空间品质、创新活力与中国城市生产率

在中国实施创新驱动发展战略助力经济高质量发展背景下,充分发挥空间品质激发创新活力、提升城市生产率的作用至关重要。本文基于新空间经济学理论,通过构建空间品质驱动城市生产率增长的空间一般均衡模型,揭示空间品质促进创新水平提升和创新人才空间配置引致城市生产率增长的双链中介机制。研究发现:空间品质对城市生产率具有显著促进作用,且创新水平提升的中介效应强于创新人才空间配置,在进行多种稳健性检验和处理内生性问题后,这一结论依然成立;创新人才空间配置机制的时间滞后效应强于当期直接效应,“留住人才”的生产率增长效果优于“吸引人才”;邻地空间品质的提升不利于本地创新水平提高和创新人才空间配置,间接降低本地生产率增长潜力。进一步研究发现,当城市具备较高的跨区消费水平和较好的创新发展环境时,空间品质对城市生产率的促进作用及其中介机制均有一定程度增强。因此,优化城市空间品质供给、促进空间品质区域一体化程度、提高空间品质跨区消费水平以及优化创新环境均是激发空间品质推动城市经济增长提质增效的重要举措。     

金融集聚、区域特征与因素影响效应——基于省级面板数据的空间计量分析

基于31个省份平衡面板数据，利用Moran指数分析金融集聚的省域空间分布特征，并通过双固定空间杜宾模型对金融集聚影响因素效应进行空间计量和效应分解。研究表明，金融集聚呈现出显著空间正相关与异质性双重特征。经济基础具有显著负向间接效应但直接效应不显著，对外开放具有正向间接和负向直接效应，区域创新具有正向直接效应但间接效应不显著，政府行为和人力资本在直接和间接效应方面均不显著，规模经济具有正向直接和负向间接效应。据此，有必要通过强化经济支撑、提升政务水平、改善金融生态、扩大对外开放以及改革人才机制等策略来提升金融集聚能力。     

中国区域经济增长格局演变与国家增长极体系建设

本文通过对中国区域经济增长的空间结构变动历程与变动态势进行统计分析,将中国区域经济增长分为经济空间集聚的酝酿起步、快速推进、巩固强化和空间扩散四个阶段,在这四个阶段,中国区域经济增长格局呈现出四大板块的相对均衡增长、七大板块的交错增长、东部主导经济增长和工业增长向西推进等特点。文章认为,随着工业化和城市化的加速推进,未来中国区域经济将形成多中心网络状的空间增长格局。从国家层面来看,应积极推进三级国家增长极体系建设。     

区域创业、空间溢出与经济增长效应研究

利用我国2005—2017年省级面板数据，基于不同类型空间权重矩阵，通过建立空间杜宾模型，研究创业水平与区域经济增长效应。结果发现: 我国区域经济水平呈现出显著的空间自相关性；机会型创业质量提高对区域经济增长具有显著拉动作用，会促进该区域内部及创业水平相近区域的经济增长，但可能抑制地理位置邻近区域的经济增长；需求型创业在一定程度上制约区域经济发展，可能抑制该区域内部经济增长，但会促进地理位置邻近区域的经济增长；在控制变量中，人力资本存量对经济增长的促进作用最强，溢出效应最大。     

资源产业依赖对中国省域经济增长的影响及其传导机制研究——基于空间面板模型的实证考察

针对现有研究忽视区域经济增长地理空间效应的重要缺陷,文章首次利用空间计量方法,以1993-2010年我国31个省份的面板数据为研究样本,对资源产业依赖如何影响我国省域经济增长及其传导机制进行了实证考察。结果表明:我国省域经济增长的空间依赖关系表现为正向的溢出效应,从空间经济视角经验考察资源诅咒命题是必要的;在考虑经济增长空间相关性之后,资源诅咒假说和条件收敛假说在我国省域层面均是成立的;资源产业依赖主要通过对技术创新水平和对外开放程度的挤出效应、削弱制造业投入的荷兰病效应以及强化政府干预程度的制度弱化效应对我国省域经济增长产生显著的间接抑制效应,其中荷兰病效应是首要原因。     

中国经济增长可持续性研究综述

金融危机对中国实体经济产生影响,关于中国经济增长的可持续性问题再次成为学界研究的焦点。国内外学者对此问题的研究主要集中在经济增长的源泉及贡献率上,并据此来判断增长是否具有可持续性。研究的方法均采用实证分析,通过对经济增长模型的统计分析,判断增长因素的比率和变动。对可持续性的判断依据基本一致,均认为TFP是经济增长可持续性的关键,但国内外学者研究的结论却大相径庭。今后的研究方向一是考虑危机和产业调整等新环境的影响,二是分析增长及在区域间可能发生转移对增长可持续性的影响,即区域增长结构可能变动的影响。     

Forecasting the price of gold

This article seeks to evaluate the appropriateness of a variety of existing forecasting techniques (17 methods) at providing accurate and statistically significant forecasts for gold price. We report the results from the nine most competitive techniques. Special consideration is given to the ability of these techniques to provide forecasts which outperforms the random walk (RW) as we noticed that certain multivariate models (which included prices of silver, platinum, palladium and rhodium, besides gold) were also unable to outperform the RW in this case. Interestingly, the results show that none of the forecasting techniques are able to outperform the RW at horizons of 1 and 9 steps ahead, and on average, the exponential smoothing model is seen providing the best forecasts in terms of the lowest root mean squared error over the 24-month forecasting horizons. Moreover, we find that the univariate models used in this article are able to outperform the Bayesian autoregression and Bayesian vector autoregressive models, with exponential smoothing reporting statistically significant results in comparison with the former models, and classical autoregressive and the vector autoregressive models in most cases.     

Planned adaptation in risk regulation: An initial survey of US environmental, health, and safety regulation

In principle, we want regulatory programs to be based on current realities, as reflected for example in the best knowledge of relevant experts. That would imply that old rules now on the books should be consistent with today's knowledge base, not just what was known when a rule or standard was originally set. This paper reports on a survey of US programs, examining how often existing rules are actually updated in light of better knowledge, and identifies five programs that attempt to make policy routinely adaptive. These programs exhibit what we term Planned Adaptation: they both revise rules when relevant new knowledge appears, and take steps to produce such improved knowledge. While Planned Adaptation is rare, it is used in several nationally prominent programs, including air pollution, airplane safety, and drug safety. Planned Adaptation is a policy tool that deserves more attention.     

The greenhouse effect: Damages,costs and abatement

The buildup of so-called greenhouse gases in the atmosphere — CO₂ in particular-appears to be having an adverse impact on the global climate. This paper briefly reviews current expectations with regard to physical and biological effects, their potential costs to society, and likely costs of abatement. For a worst case scenario it is impossible to assess, in economic terms, the full range of possible non-linear synergistic effects. In the most favorable (although not necessarily likely) case (of slow-paced climate change), however, it seems likely that the impacts are within the affordable range, at least in the industrialized countries of the world. In the third world the notion of affordability is of doubtful relevance, making the problem of quantitative evaluation almost impossible. We tentatively assess the lower limit of quantifiable climate-induced damages at $30 to $35 per ton of CO₂ equivalent, worldwide, with the major damages being concentrated in regions most adversely affected by sea-level rise. The non-quantifiable environmental damages are also significant and should by no means be disregarded.The costs and benefits of (1) reducing CFC use and (2) reducing fossil fuel consumption, as a means of abatement, are considered in some detail. This strategy has remarkably high indirect benefits in terms of reduced air pollution damage and even direct cost savings to consumers. The indirect benefits of reduced air pollution and its associated health and environmental effects from fossil-fuel combustion in the industrialized countries range from $20 to $60 per ton of CO₂ eliminated. In addition, there is good evidence that modest (e.g. 25%) reductions in CO₂ emissions may be achievable by the U.S. (and, by implication, for other countries) by a combination of increased energy efficiency and restructuring that would permit simultaneous direct economic benefits (savings) to energy consumers of the order of $50 per ton of CO₂ saved. A higher level of overall emissions reduction — possibly approaching 50% — could probably be achieved, at little or not net cost, by taking advantage of these savings.We suggest the use of taxes on fossil fuel extraction (or a carbon tax) as a reasonable way of inducing the structural changes that would be required to achieve significant reduction in energy use and CO₂ emissions. To minimize the economic burden (and create a political constituency in support of the approach) we suggest the substitution of resource-based taxes in general for other types of taxes (on labor, income, real estate, or trade) that are now the main sources of government revenue. While it is conceded that it would be difficult to calculate the optimal tax on extractive resources, we do not think this is a necessary prerequisite to policy-making. In fact, we note that the existing tax system has never been optimized according to theoretical principles, and is far from optimal by any reasonable criteria.During the academic year 1989–90 Dr. Ayres was at the International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria.During the summer of 1989 Mr. Walter was a member of the Young Scientists' Summer Program at IIASA.     

SCIENCE AND INDUSTRY: TRACING THE FLOW OF BASIC RESEARCH THROUGH MANUFACTURING AND TRADE

This paper describes flows of basic research through the US economy during the late 20th century. In addition, the paper studies the effect of the flows on scientific papers in industries and fields. This article differs from others in its use of measures of science rather than technology. Together, its results present a picture of the structure of basic research flows in a modern, science-intensive economy. Basic research flows are large within petrochemicals and drugs, and within software and communications. Flows of chemistry, physics, and engineering are common throughout all industries – biology and medicine are almost confined to petrochemicals and drugs; and computer science is nearly as restricted to software and communications. In general, basic research flows are more concentrated within scientific fields than within industries. Our findings concerning the production of scientific papers indicate that the effect of a 1% change in academic R&D spillovers significantly exceeds that of industrial spillovers. In addition, within-field effects exceed effects between-fields, while within- and between-industry effects are roughly equal. It follows that scientific fields limit basic research flows more than industries do, perhaps because large firms implicitly span a range of industries.     

Valuing Mangrove-Fishery Linkages – A Case Study of Campeche, Mexico

This paper explores the value of mangrove systems as a breeding and nursery habitat for off-shore fisheries, focusing on mangrove-shrimp production linkages in Campeche State, Mexico. We develop an open access fishery model to account explicitly for the effect of mangrove area on carrying capacity and thus production. From the long-run equilibrium conditions of the model we are able to establish the key parameters determining the comparative static effects of a change in mangrove area on this equilibrium. We then estimate empirically the effects of changes in mangrove area in the Laguna de Terminos on the production and value of shrimp harvests in Campeche over 1980–90. Our findings suggest that mangroves are an important and essential input into the Campeche shrimp fishery, but that the low levels of deforestation between 1980 and 1990 mean that the resulting losses to the shrimp fishery are still comparatively small. Over-exploitation of the fishery due to open access conditions remains the more pervasive threat, and without better management any long-run benefits of protecting mangrove habitat are likely to be dissipated.     

An Economic Analysis and Simulation of Woodfuel Management in the Sahel

This paper presents an economic framework and a computationalmethodology for assessing the evolution of woodfuel supply costsand the spatial distribution of biomass in a Sahelian woodlandsetting. Spatial data on standing stock and the costs oftransport to market are used to construct a supply curve for fuelto a fuel-consuming location. Given an exogenously specifieddemand, the model simulates, period by period, the extraction,regeneration, and transport of wood fuels. The model is appliedto evaluate the benefits and ecological impacts of scenarios forwoodland management around the city of N'Djamena, Chad.     

Evidence on the impact of R&D and ICT investments on innovation and productivity in Italian firms

Both research and development (R&D) and information and communication technology (ICT) investment have been identified as sources of relative innovation underperformance in Europe vis-à-vis the USA. In this article, we investigate the R&D and ICT investment at the firm level in an effort to assess their relative importance and to what extent they are complements or substitutes. We use data on a large unbalanced panel data sample of Italian manufacturing firms constructed from four consecutive waves of a survey of manufacturing firms, to estimate a version of the CDM model of R&D, innovation, and productivity [Crépon–Duguet–Mairesse 1998. Research, innovation and productivity: An econometric analysis at the firm level. Economics of Innovation and New Technology 7, no. 2: 115–58] that has been modified to include ICT investment and R&D as the two main inputs into innovation and productivity. We find that R&D and ICT are both strongly associated with innovation and productivity, with R&D being more important for innovation, and ICT investment being more important for productivity. For the median firm, rates of return to both investments are so high that they suggest considerably underinvestment in both these activities. We explore the possible complementarity between R&D and ICT in innovation and production, but find none, although we do find complementarity between R&D and worker skill in innovation.     

Zvi Griliches's contributions to the economics of technology and growth*

Zvi Griliches's contributions to the economics of technology and growth are identified. Included is a discussion of his contributions on: the determinants of differences in speed of adoption of innovations; the use of patents to measure technology; the private and social returns to R&D; and spillover effects from R&D. Griliches's own evaluation of his research contribution is compared to the evaluation of others in the field, using as evidence citation counts of his works collected from the online Web of Science. Griliches's most important contribution is his 1957 Econometrica hybrid corn paper that is a foundation of the economics of technological innovation. Remarkably, the trend in annual citations to the paper has continued to increase for over 40 years. Finally, we summarize Griliches's most recent views on the practice of economics and on the most important unanswered questions in the economics of technology and growth.     

新员工主动社会化行为与组织承诺关系研究——以社会资本为中介变量

为了探索新员工主动社会化行为影响组织承诺的过程,本文对来自企业的401个有效样本进行了实证分析。本研究运用层级回归的方法,控制了人口统计变量的影响后,发现员工的搜寻信息和搜寻绩效反馈行为对组织承诺有直接的正面影响,同时,通过员工社会资本对员工组织承诺产生了间接的正面影响。社会资本在员工搜寻信息和搜寻绩效反馈行为影响组织承诺的机制中起部分中介作用。员工的关系构建行为对组织承诺没有显著影响,但对员工社会资本存在显著的正面影响。