基于BP神经网络的工程造价估测方法

本文把信息扩散原理和神经网络相结合,提出一种工程造价的估测方法,并给出计算实例。     

THE NORMALIZED CES PRODUCTION FUNCTION: THEORY AND EMPIRICS

Abstract The elasticity of substitution between capital and labor and, in turn, the direction of technical change are critical parameters in many fields of economics. Until recently, though, the application of production functions with specifically non‐unitary substitution elasticities (i.e., non‐Cobb–Douglas) was hampered by empirical and theoretical uncertainties. As recently revealed, ‘normalization’ of production‐technology systems holds out the promise of resolving many of those uncertainties. We survey and assess the intrinsic links between production (as conceptualized in a production function), factor substitution (as made most explicit in Constant Elasticity of Substitution functions) and normalization (defined by the fixing of baseline values for relevant variables). First, we recall how the normalized Constant Elasticity of Substitution function came into existence and what normalization implies for its formal properties. Then we deal with the key role of normalization in recent advances in the theory of business cycles and of economic growth. Next, we discuss the benefits normalization brings for empirical estimation and empirical growth research. Finally, we identify promising areas of future research.     

Compromised imputation in survey sampling

In this paper, a compromised imputation procedure has been suggested. The estimator of mean obtained from compromised imputation remains better than the estimators obtained from ratio method of imputation and mean method of imputation. An idea to form “Warm Deck Method” of imputation has also been suggested. Received: July 1998     

FATF全球ML&TF威胁评估及对我国的启示

2010年下半年,金融行动特别工作组(FATF)发布了第1份全球ML&TF(洗钱和恐怖融资)威胁评估报告(GTA),介绍了全球视野下ML&TF威胁及最终危害的系统性框架,并提供了用来判断和应对这些威胁的指导性方法。本文对该报告进行了翻译和研究,并提出了我国借鉴该评估框架的建议。     

IV估计的最优工具变量选取方法

IV估计的有限样本性质对工具变量的选取十分敏感,尤其是存在弱工具变量的情形。本文在Donald和Newey(2001)的基础上研究了常用的IV估计———2SLS的最优工具变量选取方法。首先通过对2SLS估计量进行Nagar分解,从理论上推导出估计量的近似MSE表达式;根据这一表达式,提出IV估计的最优工具变量选取准则,并证明选取准则的渐近有效性。模拟结果表明,本文提出的工具变量选取准则能够极大地改善2SLS估计量的有限样本表现。本研究为实证中面临的工具变量选择问题提供了理论依据。     

Studying Growth in the Modern Classical Approach: Theoretical and Empirical Implications for the Analysis of Potential Output

Abstract

The main characteristics of the modern classical approach to growth are studied with particular reference to the notion of ‘potential output’. In contrast to mainstream approaches, which consider potential output to be exogenous and supply-determined, it is here regarded as endogenous and path-dependent. A tentative analysis is carried out of the implications of such a conception in empirical research, with special reference to the effects of the crisis on potential growth. Mainstream estimation methods (especially those used by international institutions) are shown to be deeply influenced by theory, but also to provide dubious and puzzling results. Very different empirical results and policy implications may be obtained from the standpoint of the alternative theoretical framework provided by the modern classical approach. On this basis, the paper proposes that the long-term policy target should be set in terms of the rate of unemployment rather than potential output or potential growth.     

中国企业资本结构动态调整的估计方法与蒙特卡罗模拟

本文首先从计量经济学以及资本结构动态调整的视角逐一评述了资本结构部分调整模型的六种主要估计方法,即混合OLS估计法、Fama-MacBeth估计法、固定效应估计法、GMM估计法、长差分LD估计法以及双边截取Tobit估计法。然后,针对我国上市公司的实际样本使用这六种估计方法进行了实证检验。在此基础上,依据我国上市公司资本结构的分布形态,采用蒙特卡罗模拟技术来识别和判断这六种方法在估计我国上市公司资本结构调整速度中的有效性。本文发现,传统的混合OLS估计法及Fama-MacBeth估计法反而是检验我国上市公司资本结构动态调整的有效方法,其估计所得的市值杠杆平均调整速度为16.3%－20.1%。     

承接产业示范区能够推动经济发展吗？ ——基于双重差分方法的验证

基于全国295个城市2000-2014年的面板数据,利用双重差分法（Difference in Differences Estimation）验证了国家级承接产业示范区对地区经济增长的影响。研究表明,国家级承接产业示范区的设立能够显著推动地区生产总值和地区人均生产总值增长,严格稳健性检验下的结论仍然成立;进一步分析发现,国家级承接产业示范区对经济增长的影响符合“边际效应递减”规律,对经济发展相对较好、禀赋较优地区的推动作用要小于经济基础薄弱、无明显禀赋优势地区。这一结论为规模推广国家级承接产业示范区战略,更好平衡区域发展、把握将来产业转移大潮提供了借鉴意义。     

经济适用房空间布局分析——以北京市为例

经济适用房的建设和布局对城市空间结构和居住者出行具有重要影响。首先采用Kernel密度估计方法计算了北京不同时期经济适用房在不同空间上的建设规模密度,分析其空间布局特征;其次,从经济适用房与地价、交通和主要就业地的相互关系分析经济适用房空间布局的演变。研究表明,北京经济适用房空间布局经历了逐步调整的过程,前期主要分布在城市北部城乡结合地带,后期考虑居民交通出行和到工作地方便等因素,在城市四周较均匀的配置和建设。总体来说,北京市经济适用住房基本分布在城市郊区,就业地与居住地相距较远的矛盾依然突出。建议今后经济适用房空间布局应更加注重主要就业地和居民交通出行的最佳匹配。     

Investigation of the costly-arbitrage model of price formation around the ex-dividend day in Norway

We estimate the costly-arbitrage model of Boyd and Jagannathan [Boyd, John, and Jagannathan, Ravi, 1994, Ex-Dividend Price Behavior of Common Stocks, Review of Financial Studies 7, 711–741.] using Norwegian stock market data. Taxable distributions take place at two separate dates, one that entails the distribution of an imputation-tax credit and another the distribution of the cash dividend. We find that the costly-arbitrage model is consistent with observed stock returns around the ex-dividend day, but the model cannot explain the return patterns around the distribution of the tax credit. We conclude that uncertainty about the cash flows prevents arbitrage.