More on Middlemen: Equilibrium Entry and Efficiency in Intermediated Markets

This paper generalizes Rubinstein and Wolinsky's (1987) model of middlemen (intermediation) by incorporating production and search costs, plus more general matching and bargaining. This allows us to study many new issues, including entry, efficiency, and dynamics. In the benchmark model, equilibrium exists uniquely and involves production and intermediation for some parameters but not others. Sometimes intermediation is essential: the market operates if and only if middlemen are active. If bargaining powers are set correctly equilibrium is efficient; if not there can be too much or too little economic activity. This is novel, compared to the original Rubinstein–Wolinsky model, where equilibrium is always efficient.     

蔬菜流通主体成本构成与收益分配实证研究

由于中间商在以批发市场为核心的蔬菜流通模式中放大了流通成本,番茄从生产端到零售终端,流通过程发生累计成本占零售价格的65.8%,流通成本费用占流通总成本的67%,扣除流通成本费用,流通中间商分享流通纯利润是生产者种植利润的1.9倍,其中批发商利润是生产者种植利润的38.4%,占流通纯利润的20%,超市供应商利润是生产者利润的64.9%,占流通纯利润的34%,超市(第三方配送)盈利是生产者利润的87.6%,占流通纯利润的45.9%。本文认为流通成本对生产者和消费者的挤兑,是体制成本、效率损失、组织化水平不高、信息不能"闭合"传递共同作用的结果,同时生产资料的高涨助推了矛盾的凸显。     

农户林产品交易中间商选择影响因素分析——以云南省348户农户为例

根据云南省348户农户林产品交易的调查问卷,采用描述性统计分析方法和二元Logistic方法分析了林改后农户林产品交易的现状和农户选择中间商交易的主要影响因素。结果表明:农户是否参加培训、交易频率、运输的难易程度和技术适用度对农户林产品是否选择中间商具有显著的正向影响;户主是否为村干部、亲戚朋友是否从事相关工作、林地面积、林产品种类和林产品的品质认证情况对农户林产品交易是否选择中间商具有显著负向影响。然后,针对农户在选择中间商销售林产品的过程中存在的问题,提出相应的对策建议。     

Articulation work from the middle—a study of how technicians mediate users and technology

This article studies the work performed by technicians in a large demonstration project, EcoGrid 2.0, in the Danish island Bornholm. Based on observations of household visits conducted by technicians, we demonstrate how these act as ‘middlemen’, mediating and linking together the smart technology of the demonstration and the involved users. Formally, technicians’ work is to keep users online; however, they also perform a number of invisible tasks to keep users engaged and active. Our ethnographic study shows two broad categories of invisible work: first, technicians continually facilitate the willingness of users, recurrently affirming the social contract between users and demonstration project. Second, technicians facilitate the abilities of users by improvising informal training sessions of how to operate the system. These findings are used to discuss the importance of invisible articulation work of technical service workers in large scale real‐world experiments.     

集聚型中间商:对专业市场交易中介效应的理论解释

本文利用中间商理论分析工具,从微观视角揭示了专业市场交易中间人作用的内在机理。基于对浙江绍兴中国轻纺城经营户和相关企业的万余份问卷调查,对专业市场交易中介效应进行了经验分析,结果表明通过降低交易双方搜寻成本、提高交易配比效率,专业市场有效发挥着交易中间人的作用;生产商选择专业市场作为产品销售主渠道的行为、批发商空间分布广度与市场信息、物流等服务完善程度正相关。     

Efficient Selection and Insider Contracting Groups: a Comment on the Yarbrough & Yarbrough Paper

Beth & Robert Yarbrough's paper reviews and augments an extensive literature analyzing how insider trading groups support the process of exchange. They argue that these groups efficiently adapt to changes in the transacting environment. Yarbrough & Yarbrough's argument is compelling for groups operating in a free and open civil society but not when competition among groups is impaired by barriers to entry and externalities. This article considers whether insider trading groups are able to reach a steady-state equilibrium and presents a number of historical and contemporary examples in which insider trading groups plant the seeds of their own destruction.