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Abstract

This paper examines some of the economic and econometric issues that arise in attempting to measure the degree of concentration in an industry and its dynamic evolution. A general axiomatic basis is developed. We offer new measures of concentration over aggregated periods of time and provide a sound statistical basis for inferences. Concentration is one aspect of the problem of measuring “market power” within an industry. Modern economic analysis of antitrust issues does not focus only on the level of concentration, but still must examine the issue carefully. We contrast concentration at a point in time with a dynamic profile of change in the distribution of shares in a given market. Our methods are demonstrated with an application to the US steel industry.     

Parameter estimation and inference with spatial lags and cointegration

This article studies dynamic panel data models in which the long run outcome for a particular cross-section is affected by a weighted average of the outcomes in the other cross-sections. We show that imposing such a structure implies a model with several cointegrating relationships that, unlike in the standard case, are nonlinear in the coe?cients to be estimated. Assuming that the weights are exogenously given, we extend the dynamic ordinary least squares methodology and provide a dynamic two-stage least squares estimator. We derive the large sample properties of our proposed estimator under a set of low-level assumptions. Then our methodology is applied to US financial market data, which consist of credit default swap spreads, as well as firm-specific and industry data. We construct the economic space using a “closeness” measure for firms based on input–output matrices. Our estimates show that this particular form of spatial correlation of credit default swap spreads is substantial and highly significant.     

市场分割与地区经济收敛关系的实证分析——基于动态面板纠偏最小二乘虚拟变量法的估计

使用动态面板纠偏虚拟最小二乘虚拟变量法,对市场分割同地区经济收敛间的关系进行实证研究发现:中国经济不存在绝对收敛,在控制了物质资本存量和人力资本后,条件收敛特征明显;在控制了市场分割和经济开放程度后,收敛特征更加显著;市场分割对经济增长的影响呈现非线性特征:当市场分割程度较低时市场分割程度的提高有利于经济增长;当市场分割程度较高时,市场分割程度的提高则会阻碍经济增长.此外,国内市场和国际市场之间存在替代关系.     

我国地区间资本要素市场分割状况:测算与分析

在完全竞争市场假设下,不同地区资本回报率应趋向统一。基于这一前提,本文首次将微观数据汇总到地区层面,借鉴“价格法”的思想,基于“市场形成价格,价格引导资源配置”提出资本要素市场分割测算方法。本文使用1998—2013年的工业企业数据库,分别在省份、地市层面测算工业、重工业、轻工业、高端装备制造业、高技术产业、战略性新兴产业、装备制造业的全国资本要素市场及省份内资本要素市场的市场分割程度。研究发现,第一,整体来看,1998—2013 年各类资本要素市场分割程度大幅度下降,下降幅度在50%左右,其中高端装备制造业、高技术产业下降尤为明显。分阶段来看,资本要素市场在第一阶段(1998—2002年)及第二阶段(2002—2008年)均趋于整合。第二,基于地级市层面的测算发现,经济发展水平相对较高地区的市场分割下降幅度大于经济发展水平相对较低地区,且在样本期末前者的市场分割程度低于后者。第三,基于省份层面的测算发现,全国各行业市场分割平均下降幅度大致在49%~63%之间,东部沿海地区市场分割程度相对低于内陆地区。第四,增加市县级政府税收共享比例在调动地方积极性的同时会加剧市场分割,而中央政府在更大范围的基础设施建设将推动资本要素市场整合。     

基于灰色关联的西部煤炭产业集中度影响因素研究

在概述西部原煤产量及其矿井类型与数量变化趋势的基础上,利用2003-2010年相关时序数据测度了西部煤炭产业在这一时期的集中度。随后,运用灰色关联理论,分析了期初集中度、生产扩张能力、进入壁垒、市场容量等相关因素与西部煤炭产业集中度的灰色关联程度。研究表明:期初集中度与市场容量是影响西部煤炭产业集中度诸多因素中最为重要的两个因素。在进一步分析产生这一结果深层原因的基础上,提出了提高西部煤炭产业集中度的政策建议。     

A looser cointegration concept using fractional integration parameters and quantification of market responsiveness

Many economic variables are fractionally integrated of order d, FI(d) with unequal d's. For modeling their long-run equilibria, we explain why the usual cointegration fails to exist and the unit root type tests have low power. Hence, we propose a looser concept called “tie integration”. A new numerical minimization problem reveals the value of d in the absence of tie integration, denoted by d_null. We use the d from residuals of a regression, as well as, d_null to devise a new index called strength of tie (SOT). An application quantifies market responsiveness.     

经济政策不确定性如何影响金融市场间的流动性协同运动？——基于中国金融周期的视角

金融市场间流动性出现高协同运动是发生危机传染的重要表现之一，因此，针对流动性动态联动效应的研究显得极为重要。本文基于中国金融市场数据测算了2003-2018年间我国股市、债市流动性，并对Colacito等（2011）的混频数据抽样动态条件相关系数模型（DCC-MIDAS）进行了扩展，同时从金融周期视角出发，运用扩展后的模型考察了经济不确定性在不同时间区间内对于流动性波动率和相关性是否存在不同的作用效果。研究结果表明，相较于单因子混频模型，引入经济政策不确定性的多因子混频模型可以更好地捕捉我国股债两市相关性的动态变化；同时，经济政策不确定性的提高会降低股债两市流动性的正相关性，但这一作用效果会在金融周期的拐点处转为加强两者的正相关性。本文不仅为讨论股债两市联动效应提供了流动性的新视角，也为金融市场风险监管提供了重要的参考依据。     

陕西省服务业发展研究

服务业现代化程度的测评是目前研究涉及较少的领域。从分析陕西省服务业发展水平和结构入手,首次提出服务业现代化指数概念,并结合2005年经济普查的数据对陕西省服务业各行业的现代化水平及其经济效益进行了初步测评。在定量分析的基础上得出了陕西省服务业内部各行业经济效益参差不齐的结论。从整体上看,其经济效益还较低,因而提高服务业的经济效益应该成为陕西省发展服务业的主要努力方向。     

西安市三次产业投入产出结构实证分析

为了准确认识西安市产业结构的现状,为相关部门进行产业调整提供依据,在对西安市2007年9部门投入产出表进行归纳的基础上,运用投入产出分析法对三次产业作了投入结构和产出结构分析,并从数量角度说明西安市三次产业之间的经济技术联系及比例关系.实证分析表明:目前第二产业对经济发展的拉动力和支撑力最强;第三产业的地位日益提高;第一产业的基础地位不可动摇.三次产业要协调发展.     

Share equations in econometrics: A story of repression,trustration and dead ends

Share equations play an important role in applied economic research, notably in marketing and demand analysis. Both market shares and budget shares have been used as dependent variables in econometric models which were partly motivated by microeconomic theory. However attempts of econometricians (and other statisticians) to treat share equations adequately led mostly to unsatisfactory approaches: Some researchers although admitting that shares satisfy a sum constraint simply repressed the fact that shares cannot be normally distributed. Some researchers looked in vain for a stochastic specification which at the same time is consistent and allows a flexible covariance structure. Last not least almost nobody has properly taken care of additional problems arising from dynamic share models. The paper discusses these three issues and proposes a possible way out of this dilemma which was first suggested by Aitchison (1982) and has been applied to econometric demand analysis by Considine and Mount (1984). Demandtheoretic implications as well as methods of estimation are discussed. An example using German import data illustrates some of the results. Research for this paper is financially supported by Deutsche Forschungsgemeinschaft, SFB 178 “Internationalisierung der Wirtschaft” at the University of Konstanz. Some results reported in this paper have been achieved jointly with Karl Ringwald whose permission for using unpublished joint work is gratefully acknowledged. Critical remarks by an anonymous referee helped to improve the exposition of the paper.     

中国煤炭产业产能利用率估算与演变特征研究

基于产能利用率的概念,运用超越对数成本函数估算了中国煤炭产业1994-2012年的产能利用率,并分析了其演变特征。研究发现:总体上中国煤炭产业的产能利用率较低,1994-2012年年均产能利用率仅为76.96%,提高产能利用率以降低固定成本的潜力较大;其次,中国煤炭产业产能利用率呈现出明显的周期性波动,近年来与经济波动的关联更紧密;最后,2012年中国煤炭产业产能利用率、煤炭价格和规模以上煤炭企业经济效益均大幅下降,煤炭产业产能过剩严重。进一步分析表明,产能集中释放、需求不振和煤炭进口冲击共同造成了中国煤炭产业2012年的严重产能过剩。     

信贷规模、效率和结构对中国经济增长驱动力的影响分析——基于LMDI乘法分解

基于马克思主义经济学的经济增长理论,构建了由预付资本规模和预付资本社会再生产组织效率决定的市场经济社会再生产理论模型。基于理论模型,借助LMDI乘法分解对以信贷为代表的货币预付资本的规模、效率和结构对中国经济增长的驱动力进行了统计分析。分析认为：中国以信贷为主要代表的货币预付资本增加对经济增长存在驱动力,以信贷规模为代表的信贷投入是驱动经济增长的主要因素,信贷效率在没有外部扰动年份对经济增长呈现正向贡献,信贷的区域结构变化对中国当前经济增长不具备驱动力。     

工业机器人使用与制造业就业：来自中国的证据

本文使用我国2006-2017年制造业分行业数据，实证研究了工业机器人使用对于制造业就业的影响。结果显示，工业机器人使用对制造业行业存在就业效应，其中对岗位数量有显著的负向冲击，工业机器人保有量每上升1%，就业岗位减少约4.6%；对工资水平的影响整体上不明显。在考虑了劳动力市场的动态调节后，工业机器人使用对就业岗位的负面影响仍然存在，并随着“工业4.0”概念的提出有所增强，对工资水平的影响则表现出时间异质性。进一步地，本文尝试使用工具变量解决潜在的内生性问题，结果稳健。最后，文章还探讨了工业机器人就业效应的行业异质性。本文的发现有助于正确认清“机器换人”对我国制造业就业市场的全面影响，并为引导人工智能技术的发展和确保就业稳定提供相应的政策建议。     

Celebrating Twenty Years of a Serials Column

A co-editor of “The Balance Point” column looks back at its twenty-year history, its current function and its future in serving the serials professional and scholarly community. The author examines how the column emerged as an idea by then Serials Review editor Cindy Hepfer in 1988 to be a forum on important serials issues for practitioners who might not otherwise write formally on these topics. The column has continued though the 1990s and 2000s to provide that function, as well as serve as an important place where authors are invited to explore serial issues much in need of a balanced approach. The author shares comments from past “Balance Point” column editors, John Riddick, Mary Beth Clack, Ellen Finnie Duranceau, Karen Cargille, Markel Tumlin, and Kay Johnson on how they regarded the column, the rewards and challenges they faced, and how they see the future of this format in an evolving electronic communication milieu.     

国内市场一体化对出口技术复杂度的影响及作用机制

本文从中国经济特有优势出发,系统梳理和归纳了国内市场一体化影响出口技术复杂度的理论机制,并利用中国2003-2016年30个省份（西藏除外）的面板数据,构建中介效应模型,对理论预期进行了实证检验。研究结果表明：国内市场一体化显著促进了出口技术复杂度的提升,并且随着时间的推移,这种促进作用逐渐增强。市场一体化对出口技术复杂度的影响存在行业及区域差异性。市场一体化对技术密集型行业出口技术复杂度的提升作用最为突出。内陆地区的市场一体化系数显著为正,而沿海地区市场一体化的正向影响效应不显著。市场一体化除了直接对出口技术复杂度发挥促进作用,还可以通过技术创新效应、需求驱动效应、制度改进效应等机制促进出口技术复杂度提升,其中技术创新的中介效应最为有效。本文的研究结论对中国推进国内统一大市场建设,实现贸易强国目标和经济转型发展具有借鉴意义。     

银行业“松绑”与企业“走出去”:基于中国工业企业数据的分析

中国银行业在金融体系中起着关键性的作用,一直是金融发展的重要部分。进入21世纪以来,中国银行业以国有银行为主的结构出现了重大变革,银行业竞争程度不断提高。关于银行业竞争的经济效应存在“市场势力假说”和“信息假说”两个假说,本文尝试在银行准入管制放松政策的背景下和鼓励企业“走出去”的情境下,利用匹配的微观层面数据来实证检验以上的假说,主要得到以下几个结论:首先,银行业“松绑”有助于企业“走出去”; 其次,采取倾向性得分匹配方法应对样本选择问题, 并用工具变量方法应对内生性问题后,这一结论依然成立;最后,银行业“松绑”引起的融资成本下降是银行业“松绑”影响企业“走出去”的重要渠道,企业“走出去”的分析结果也支持了中国情境下银行业“松绑”的“市场势力假说”。本文的研究为银行业改革与企业对外直接投资的关系提供了重要证据,并验证了中国情境下银行业“松绑”的“市场势力假说”和“信息假说”,有助于更加深刻地理解和评估中国银行业改革的经济效应,对更好推动“一带一路”建设有着重要意义。     

Longitudinal dynamic analyses of cognition in the health and retirement study panel

The purpose of this paper is to highlight some classic issues in the measurement of change and to show how contemporary solutions can be used to deal with some of these issues. Five classic issues will be raised here: (1) Separating individual changes from group differences; (2) options for incomplete longitudinal data over time, (3) options for nonlinear changes over time; (4) measurement invariance in studies of changes over time; and (5) new opportunities for modeling dynamic changes. For each issue we will describe the problem, and then review some contemporary solutions to these problems base on Structural Equation Models (SEM). We will fit these SEM to using existing panel data from the Health & Retirement Study (HRS) cognitive variables. This is not intended as an overly technical treatment, so only a few basic equations are presented, examples will be displayed graphically, and more complete references to the contemporary solutions will be given throughout.     

Modeling and forecasting realized covariance matrices with accounting for leverage

The existing dynamic models for realized covariance matrices do not account for an asymmetry with respect to price directions. We modify the recently proposed conditional autoregressive Wishart (CAW) model to allow for the leverage effect. In the conditional threshold autoregressive Wishart (CTAW) model and its variations the parameters governing each asset's volatility and covolatility dynamics are subject to switches that depend on signs of previous asset returns or previous market returns. We evaluate the predictive ability of the CTAW model and its restricted and extended specifications from both statistical and economic points of view. We find strong evidence that many CTAW specifications have a better in-sample fit and tend to have a better out-of-sample predictive ability than the original CAW model and its modifications.     

VIX指数对股票市场间联动性影响的实证研究

近期金融危机频繁发生,国际金融市场之间的动态联动性成为一个重要的研究课题。以往学者大都直接研究金融市场间的相关性,而忽略了外生金融变量对金融市场间相关性的影响。本文将对上述问题进行研究,借鉴Silvennoinen和Terasvirta(2015) STCC模型的思想,假定Copula参数受外生变量的影响,建立时变动态Copula模型——ST-VCopula模型,并基于该模型探究市场波动率（VIX指数）对股票市场之间相关性的影响,进而对几个国家的股票指数数据进行了实证分析。实证结果表明VIX指数对股票市场间联动性产生了显著的影响。VIX指数的获取简单便捷且更为直观,为市场间动态联动性的研究提供了另一种途径,可以为投资者在进行分散投资等金融活动时提供一定的指导和建议。     

中国城镇化进程与经济增长关系的实证研究

 以我国1978-2009年城镇化率和人均GDP年度时间序列数据为基础,建立反映城镇化水平和经济增长动态关系的向量自回归(VAR)模型;在VAR模型的基础上,运用脉冲响应函数和方差分解分析了城镇化进程与经济增长相互之间的动态影响。为了弥补时间序列数据只包含时间和指标两维信息的缺陷,进一步采用2000-2009年我国31个省市的城镇化率和人均GDP的面板数据,利用横截面、时间和指标三维信息对两者之间的关系进行分析。通过运用面板数据的单位根检验和面板数据协整检验,得出我国城镇化进程与经济发展水平之间存在长期稳定的均衡关系。在此基础上,建立面板数据固定效应变系数模型,从弹性角度分析,认为我国城镇化率每提高一个百分点,可以维持7.1%的经济增长。