Aggregation of Directional Distance Functions and Industrial Efficiency

Three main objectives are pursued in this paper. First, we intend to analyze the aggregation problem of directional distance functions from a constructive viewpoint. We provide necessary and sufficient conditions concerning the structural properties of the production technology and of the nature of groups of firms. Indeed, exact additive aggregation holds for a linear technology and for a direction solely defined in the output space. Second, since these conditions are somewhat restrictive, we are interested in providing a measure for the aggregation bias through the relationship between industrial and structural technical efficiency. Finally, we show that this aggregation bias is a lower bound for industrial allocative efficiency.     

河南省第三产业结构发展趋势预测与灰关联分析

笔者通过运用等维灰数递补模型对河南省第三产业产值、城镇居民人均可支配收入、交通运输仓储及邮电通信业、批发和零售贸易餐饮业、金融保险业、房地产业产值进行预测，认为河南第三产业结构自“十五”后趋于合理，房地产业、公交邮电通讯业、批零商业等日趋重要，相应的对策是应在保持这些产业优势的基础上，大力发展一些新行业，促进河南第三产业健康发展和人民生活水平持续提高。     

“一带一路”倡议下中国口岸出入境货运量的时空格局演变探究

口岸作为国家指定的对外开放门户,承担着国与国之间货物运输和人员往来的重要功能。"一带一路"倡议的实施促进了我国口岸的发展,带动了口岸经济与区域经济的发展,反过来进一步加强了与"一带一路"沿线国家的合作。本文利用口岸运行指标中的出入境货运量数据,借助探索性空间数据分析方法,对我国2011—2017年31个省(区、市)的口岸出入境货运量的时空格局进行分析。结果表明:"一带一路"倡议提出后,尤其是2015年后,我国口岸出入境货运总量呈现快速增长态势且存在显著的空间正相关性;三类口岸(水运、陆运和空运口岸)中,水运口岸存在更显著的、更强的空间相关性;各类口岸出入境货运量中,东部沿海地区水运呈现正向空间集聚现象,西部沿边地区陆运呈现极化现象。此外,本文对全国31个省(区、市)的地区货运总量也进行了空间动态分析,发现也存在空间相关性,且集聚效应在"一带一路"倡议提出后不断增强。在此基础上,为了更好地服务于"一带一路"建设,本文提出了提升各类口岸运输能力的相关对策建议。     

关税减让政策对我国进口的影响

中国加入WTO后,关税减让协议的逐步实行对我国进口贸易产生了极大影响.研究结果表明,关税与我国进口贸易额之间存在着高度的负相关关系,在影响我国进口效应的诸多因素中.关税起到了主要作用,但并非唯一因素.而关税减让在影响我国进口商品结构方面的作用不大.可见,在优化我国进口商品结构方面还需要其他政策措施的辅助与调整.     

Inter-basin water transfers under uncertainty: Storage capacity and optimal guaranteed deliveries

This paper deals with water transfers between jurisdictions not claiming riparian rights to the same water source, and taking place through straightforward sales. Taking into account the uncertain nature of water surpluses, we investigate, within a partial equilibrium framework, the implications of a third party's provision of storing facilities upon the potential supplier's decision whether, and to what extent, it is worthwhile to guarantee a constant amount of water exports. The analysis suggests that there exists a minimum storage capacity below which the potential supplier will never find it profitable to divert a constant amount of water outside his boundaries; the greater the uncertainty about future surpluses and/or internal costs due to even occasional water shortages resulting from the water export commitment, the higher the required minimum storage capacity will be. Above this minimum, an increase in the capacity would be better for the surplus agent, but in a situation in which water surplus is expected to decrease over time, increases in storage capacity would make him willing to guarantee a smaller amount of water deliveries.This work has been carried out under the auspices of the European Science Foundation's research program Sharing fresh water resources in the Mediterranean region: An economic perspective. Previous versions have been presented at ESF workshops held at the Universities of Haifa, Padova and Crete. Financial support from MURST (funds 40% — 1992) is gratefully acknowledged. We wish to thank Nunzio Cappuccio, Haluk Akdogan, Karl Mäler, Mordechai Shechter, Naomi Zeitouni, and two anonimous referees for helpful comments. The usual disclaimer applies.     

Portfolio Optimization under Lower Partial Risk Measures

Portfolio management using lower partial risk (downside risk) measures is attracting more attention of practitioners in recent years. The purpose of this paper is to review important characteristics of these riskmeasures and conduct simulation using four alternative measures, lower semi-variance, lower semi-absolute deviation, first order below targetrisk and conditional value-at-risk.We will show that these risk measures are useful to control downside risk whenthe distribution of assets is non-symmetric. Further, we will propose a computational scheme to resolve the difficultyassociated with solving a large dense linear programming problems resulting from these models. We will demonstrate that this method can in fact solve problems consisting of10⁴ assets and 10⁵ scenarios within a practical amount of CPU time.     

两个灰距离空间(■d)(■.ρ)

本文在邓聚龙教授提出的层次型灰数和信息型灰数——经典有理灰数的基础上,用近代分析的方法,给出两种灰距离空间(/.d)和(/.p),并结合几何直观将两种灰距离进行了比较。     

Real estate return correlations: Real-world limitations on relationships inferred from NCREIF data

Correlation estimates for returns between individual properties are subject to large inherent uncertainties due to limits on the amount of data that is likely to be available for the foreseeable future. After allowance for correlation sampling error, it is impossible to distinguish on an ex ante basis between the risk-reduction capabilities of mean-variance portfolio selection models and naive diversification without regard to property type or geographical location. The naive portfolio diversification strategies of typical institutional real estate portfolio managers are rational responses to limitations on the informational content of statistical analyses of historical real estate data.     

基于灰色关联分析的施工方案优选研究

施工方案的选择不仅直接影响项目利润的大小，更会关系到项目的成功与失败。本文在充分考虑施工方案影响因素的基础上，选择施工方案评价指标，利用层次分析法确定各评价指标的权重。建立灰色关联分析模型，构造理想方案。在分析各拟选施工方案与理想方案关联度的基础上确定最优方案，并结合实例进行了阐述。     

企业主体性产权理论的构建 --相关和自主统一的属性所有权

企业是市场经济活动的主体，应该具有其主体属性，并且正是其主体属性决定它的主体地位和作用，并形成主体性产权。但是，学术界缺乏对这个问题的研究，主要是因为受西方经济学传统的限制，要突破这种限制必须把经济学与管理学结合起来进行研究，以构建企业主体性产权理论。企业主体性产权是其相关属性产权与自主属性产权的统一。企业相关属性及其产权是基础和结果，主要说明企业主体性产权的共性；企业自主属性及其产权是原动力和境界，主要说明企业主体性产权的个性。它们的互补和统一突出地体现在企业家及其产权上。企业主体性产权的目的是在防止“蛋糕”缩小的同时把“蛋糕”做大，其核心是基于相互关系的约束而进行自主创造的激励，其模型的运行特点是协同一自主创造。企业主体性产权理论的应用，可以保证和促使中国企业循着超越自然历史发展。