Learning,forecasting and optimizing: An experimental study

Rational Expectations (RE) models have two crucial dimensions: (i) agents on average correctly forecast future prices given all available information, and (ii) given expectations, agents solve optimization problems and these solutions in turn determine actual price realizations. Experimental tests of such models typically focus on only one of these two dimensions. In this paper we consider both forecasting and optimization decisions in an experimental cobweb economy. We report results from four main experimental treatments: (1) subjects form forecasts only, (2) subjects determine quantity only (solve an optimization problem), (3) they do both and (4) they are paired in teams and one member is assigned the forecasting role while the other is assigned the optimization task. All treatments converge to Rational Expectation Equilibrium (REE), but at different speeds. We observe that performance is the best in treatment 1 and the worst in Treatment 3. We further find that most subjects use adaptive rules to forecast prices. Given a price forecast, subjects are less likely to make conditionally optimal production decisions in Treatment 3 where the forecast is made by themselves, than in Treatment 4 where the forecast is made by the other member of their team, which suggests that “two heads are better than one” in term of the speed of finding the REE.     

Upstream or downstream in the value chain?

Companies in the natural resources industry (e.g., mining, timber, farming and fishery) face the dilemma of whether to focus upstream or downstream in the value chain. The literature provides arguments and empirical evidence for either position. This paper presents an analytical framework based on the neoclassical theory of the firm, for which the best competitive advantage is the one that maximizes production efficiency. It serves to formulate an optimization model for the sawmill industry, and draws the data from the largest sawmilling company in the southern hemisphere. Although one conclusion is that the company should concentrate on the upstream activities, such conclusion is not applicable to other firms, since the analysis of the upstream-downstream dilemma must focus on the individual capabilities of each firm.     

我国农产品营销渠道优化研究

农产品营销渠道问题是农产品营销研究的核心问题和学术前沿。本文从我国农产品营销渠道存在的问题着手,提出优化农产品营销渠道的三大路径,即:对现有农产品批发市场升级拓展、发展农产品流通合作组织和农产品产销一体化组织。     

The MPS parameterization under lead time uncertainty

The supply planning of assembly systems under lead times uncertainty is studied. The used criteria is the sum of the average holding cost for the components, the average backlogging cost for the finished product, and the setup cost. The decision variables are the planned lead times of components and the periodic ordering quantity. A new generalized Newsboy model gives the optimal solution under the assumption that the lead times of the different types of components follow the same distribution probability, and that the holding costs per period of the ordered quantities are the same.     

供应链的整体集成与优化研究

集成供应链的研究是目前国内外研究的热点.供应链管理所产生的真正竞争优势在于它能有效地管理好整个供应链,即整体的集成与优化.因此,采用大系统理论来解决供应链管理中的集成与优化不仅十分必要而且十分恰当;同时,对供应链的协调与集成优化作进一步研究,使之更加敏捷、更加富有柔性地快速响应顾客的个性化需求,也是未来一个十分重要的研究课题.     

平面连杆机构的优化设计

利用单变参数（辅助角）按最佳传动角及最大行程速度变化系数对曲柄摇杆机构进行优化设计，提高了机构设计质量，方法实用可行。     

Oracle数据库的性能优化在电信CRM系统中的应用

数据库性能的优化在基于Oracle数据库的应用系统开发过程中是相当重要的一个环节,该文讨论了Oracle数据库的性能优化在电信CRM系统中的应用,包括:数据库设计的优化,应用程序的优化.从优化的结果看,系统的响应时间明显降低,系统的效率得到提升.     

中国汽车产业组织政策思考

企业自组织理论与产业组织政策理论为汽车产业组织制定奠定了坚实理论基础。反思以往的产业组织政策,进入管制失效、过度保护、支持大企业政策落实不力、汽车消费政策不到位等问题突出。为优化汽车产业组织结构,今后汽车产业组织政策的重点必须以市场化为导向,改革汽车产业的行业管理体制;加快重点国有汽车企业产权改革;营造良好的汽车消费环境;为一些汽车厂商顺利退出创造必要条件。     

A flexible inventory model for municipal solid waste recycling

State laws mandate the recycling of municipal solid waste (MSW) across most of the United States. In order to comply, municipalities recycle quotas of materials, generally without regard to fluctuating prices. An inventory system is proposed that allows municipalities to be sensitive to materials prices as they recycle in accordance with state mandates. A dynamic model is developed that uses historical secondary material prices as exogenous inputs to minimize the net present value of MSW recycling system cost. The model provides a cost effective method for municipalities to achieve their MSW recycling targets. The savings is approximately $1.28 per ton of MSW generated as based on total MSW management costs of $13.5 per ton. The model also allows one to investigate the effectiveness of various strategies for increasing the recycling rate, including reducing the transportation cost for recyclables, supporting the market price of selected secondary materials, and landfill bans on selected materials. Our proposed model may also be used to investigate the effect of market price changes on the portfolio of materials held in inventory for recycling.     

人均收入差距导向的投资战略

除了税收手段直接调整人均收入差距之外,政府可利用投资配置来影响生产过程,进而调整人均收入差距。在总量封闭经济的框架下,本文以人均收入差距最小化为目标,通过引入多地区多产业Cobb-Douglas生产函数、劳动一资本比率、资本时变率,改造最优经济增长模型。实验表明,通过权衡不同地区、不同产业的重要程度,调整投资在不同地区、不同产业之间的配置比率,政府可缩小人均收入差距。