提高交接计量精度 降低管输原油损耗

介绍了管道输油单位工艺流程和油量计算,通过收、销油参数的对比,分析了标准器具、环境、人员等引起管输原油差量的原因,提出了如何通过采取流量计系数交接、同时加强对收、销油在体积、密度、含水等参数的监督,来提高原油交接计量精度,降低管输原油损耗。     

Asymptotic analysis for optimal investment and consumption with transaction costs

We consider an agent who invests in a stock and a money market and consumes in order to maximize the utility of consumption over an infinite planning horizon in the presence of a proportional transaction cost . The utility function is of the form U(c) = c^1-p/(1-p) for p > 0, . We provide a heuristic and a rigorous derivation of the asymptotic expansion of the value function in powers of , and we also obtain asymptotic results on the boundary of the no-trade region.Received: July 2003, Mathematics Subject Classification (1991): 90A09, 60H30, 60G44JEL Classification: G13Work supported by the National Science Foundation under grants DMS-0103814 and DMS-0139911.     

Non-grant microfinance,incentives and efficiency

I show that charging interest on funds provided by donors or investors to microfinance institutions (MFIs) can increase efficiency, the total number of loans and borrower welfare, compared to grant or concessionary funding. In a setting in which MFIs supply costly non-contractible effort, putting a price or raising the price of loanable funds strengthens the MFIs’ incentives to put effort in credit administration or monitoring, to extend more loans, and/or reduce overhead costs. This theoretical result is robust to several variations of the benchmark model allowing for an endogenous lending rate, motivated MFIs and endogenous overhead costs.     

交易成本与西部经济的发展

实施西部开发是解决中国区域经济发展不平衡问题的一项重大举措,但目前东西部的差距在进一步增大,西部经济发展面临着诸多障碍,交易成本高昂是其中一项重要原因,降低交易成本是促进西部经济快速发展的重要路径。     

生态资源环境公共产权的经济学分析

在产权制度的界定和规范引导下,生态资源经济才能实现环境友好型、可持续为主题的科学发展。历史上“公有地的悲剧”的启示不单是对产权问题的反思,而是通过设立一套巧妙的制度,以达到“量体裁衣”之功效。生态资源环境公共产权的产生是源于其稀缺性及非排他性的特质。但随着计量这种产权成本与收益的难度不断加深,环境资源体系的经济价值就越来越大。必须考虑在有效利用的前提下,重新界定产权来保证市场与主体效率目标的实现。作为现代产权制度体系的最重要的组成部分——资源类产权,它有别于企业产权制度,且它涉及利益主体的范围之广。涵盖的意义也极其深远。本文对生态资源环境这一较为特殊公共物品的产权问题用产权经济学的思维框架进行研究,从政府、企业、市场、制度四个层级,相应提出构建此类公共产权的四层规制模式,以求破解在生态环境规制过程中出现的产权失灵现象及界定不清的困局。     

交通基础设施、FDI与农村剩余劳动力转移

在分析交通基础设施及FDI影响农村剩余劳动力转移机理的基础上构建空间自回归模型,利用30个省级区域1998—2014年面板数据实证分析普通公路、铁路及FDI对农村剩余劳动力转移的影响。研究表明：普通公路有效促进农村剩余劳动力就地转移;铁路促进农村剩余劳动力跨区域转移,具体来说,东部沿海地区和西部地区铁路与农村剩余劳动力转移为倒“U”型相关关系,而在中部地区为“U”型;FDI显著促进农村剩余劳动力转移,在全国范围内FDI通过作用于铁路促进农村剩余劳动力跨区域转移。     

基于作业成本法的北京市公交车运营成本测算研究

北京公交的运营成本过高是北京市公交发展中的一个比较突出的问题,而且目前北京公交缺乏科学、精确的运营成本测算方法与体系。为解决相关问题,应该结合国内外相关研究与调研资料对北京市公交运营成本的构成体系进行确定与分析,并运用作业成本法对北京市公交运营成本展开测算研究。     

基于交通视角的新疆城市等级体系演变研究

通过主成分分析、集中度系数、非均衡系数以及改进的重力模型对新疆各城市的交通运输综合水平、复合流量的集中程度和基于复合流量的城市引力及引力节点分析,得出结论:①1985—2005年新疆城市交通运输综合水平变化明显,国道和北疆铁路沿线城市发展水平较高,发展水平较低的城市主要集中在南疆,且比较分散;②集中度系数波动明显,乌鲁木齐、克拉玛依、昌吉、阿克苏等城市对新疆客货流影响较大,而区域非均衡系数较低,呈现明显缩减的趋势;③受绿洲城镇发育程度和自然地理条件影响,各等级节点数量变化不大。乌鲁木齐、克拉玛依、昌吉、石河子在不同年份对新疆各城市的影响较为明显,节点等级较高。④基于交通视角的城市体系呈现出交通运输中心区域不断强化,二级节点城市变化明显,经过20年的演变,基本形成了以乌鲁木齐都市圈为核心,以石河子为次级中心,以喀什和米泉为三级中心,以克拉玛依、伊宁、乌苏、库尔勒为重要节点的城市体系。     

Ultimate Government Control Structures and Firm Value: Evidence from Chinese Listed Companies

We show that 70% of Chinese listed companies are ultimately controlled by government agencies, thereby indicating that state ownership remains widespread in China's stock markets. Three questions are considered that are related to government control structures and their impact on firm value: (1) how do government agencies maintain their control of listed companies; (2) what are the impacts of different government control structures on firm value; and (3) are these impacts different in local government and central government-controlled firms? We find that the Chinese government controls listed companies directly or indirectly through solely state-owned enterprises (SSOEs). Taking into account the trade-off between political and agency costs, we show that firm value increases when some control rights are decentralized from the government to state-owned enterprises (SOEs). Moreover, decentralization improves significantly the performance of local government- controlled, but not central government-controlled firms.     

Market maker competition and price efficiency: Evidence from China

We test the relationship between market maker competition and stock price efficiency. Using the number of market makers as a proxy for competition, the results show a strong positive correlation between competition and stock price efficiency. Moreover, price efficiency is higher when competing market makers have higher research ability. We suggest that market maker competition increases price efficiency through two channels: 1) Competition decreases transaction costs, and 2) Uninformed market makers learn from orders submitted by informed market makers through competition. The latter happens only in the group of market makers with higher experiences. The results imply that the price efficiency can be improved by enhancing the competition of market makers with high research ability and experiences.