A STOCHASTIC MODEL FOR THE OPTIMAL REPLACEMENT OF RUBBER TREES

Recognizing the lack of realism in optimal replacement analyses that assume constant prices and yield patterns over time, a stochastic model appropriate to rubber production is developed. Data drawn from Peninsular Malaysia are used to implement the model. The results suggest that efforts should be directed towards establishing bench mark maximum annuities as guides to more economic replanting decisions rather than emphasizing earlier replanting per se. The significance of price stabilization policies also becomes evident.     

A CONCEPTUAL FRAMEWORK FOR ANALYSIS OF MARKET EFFICIENCY

Important agricultural marketing policies and decisions are constantly before industry and government. Much market research is being supported. There is a need to “bridge” research with policy. The core of this paper is to develop a conceptual framework that spans the needed analysis of marketing efficiency. The basic point is that marketing policy must focus on both competition and physical operations. The analysis of this paper builds upon Clark's concept of workable competition and Sosnick's extension to the concept of effective competition. Market efficiency is separated into operational efficiency and exchange efficiency components; the determinants of each component are diagnosed and analyzed in terms of costs and pricing. While the agricultural marketing process produces increments of product form, space, and time utility, costs are incurred. Cost analysis is central to the notion of operational efficiency; cost levels depend upon market organization and the feasible set of market logistics. Exchange efficiency refers primarily to price; the effectiveness with which price reflects costs depends upon market structures and the applicable competitive strategies. The conceptual framework developed in this paper integrates the preceding relationships and formalizes an approach for decisions. Trade-offs often exist between operational efficiency and exchange efficiency components of market efficiency. When a trade-off relationship exists, market efficiency is maximized by equalizing the gain in one component with the opportunity-cost loss in the other component. Le gourvernement el I'industrie font continuellemeni face à?importante décisions dans le domaine des marchés el de la politique agricloe. Ces deux groupes subven-tionnenl les recherches dans ce domaine. II y a un besoin de Her la recherche avec la politique. ?essentiel de cet article est de développer un côdre qui comprend ?analyse nécessaire pour ?efficacité du marché, le point important est que le politique du marché doit se concentrer sur le concurrence et les operations. L'analyse de cet article travail sur le théorie de concurrence réalisable de Clark et sur celle Sosnick traitant de ?Extension de la concurrence effective. ?efficacité du marché est diversé en deux éléments: ?exploitation efftcace el ?echange éfficace, les facteurs déterminant de chaque élément sont soumis à un diagnostic et à une analyse en termes du coût et du prix     

A NOTE ON SOME DIFFICULTIES IN RESPONSE ANALYSIS

Some empirical problems which tend to receive inadequate attention in response analysis are discussed. These include the variation not explained by fitted production functions, the sensitivity of optima and profits to price changes, the cost of developing production functions and the value in using them.     

INTERRELATIONSHIPS AMONGST EFFICIENCY MEASURES: A NOTE

A principal component analysis of physical efficiency criteria such as calving and lambing percentages is studied for 91 farmers in a homogeneous farming area. The first component implied that a farmer achieving a high score in one efficiency criterion, also achieves high scores in other criteria. This component, called a ‘performance index’, showed a common association with financial success in farming. This ‘performance’ factor can be included in the routine computer printouts of farm records and could furnish additional information concerning management at no extra cost.     

A FURTHER NOTE ON THE MEASUREMENT OF EFFICIENCY AND ECONOMIES OF FARM SIZE

Efficiency has a precise meaning in the case of the optimally conditions associated with the perfectly competitive norm. However, the efficiency concept loses a precise meaning and much of its usefulness under real world conditions of uncertainty and costly information since efficiency is inescapably evaluative and cannot be defined and measured independently of the goals and knowledge of the decision maker. Similarly, the concept ‘economies of size’ is shown to lose its normative significance when specialised resources and other unique aspects of the firm are taken into account. Although the economist has no objective procedure by which to measure the efficiency of entrepreneurial activity, it is argued that in the real world of uncertainty and disequilibrium, there is always scope for entrepreneurial activity in the sense of unexploited profit opportunities.     

地方财政支农支出对农业技术效率影响分析*——基于随机前沿分析方法

农业是经济可持续发展的重要保障,而农业的发展更加需要政府财政的扶持,那么作为支撑农业发展的地方财政支农支出对农业技术效率的提高是否存在着积极影响？本文使用中国31省市的2000～2011年的面板数据,运用基于对数型柯布-道格拉斯生产函数的随机前沿分析(SFA)模型,实证分析了地方财政支农支出和地区差异对中国农业技术效率的影响程度,中国农业技术效率的变化以及东、中、西部地区的农业技术效率的差异.通过实证研究得出:中国农业生产存在显著的效率损失,主要来自技术效率损失,但从中国农业技术效率的变化趋势看,中国农业技术效率年均增长3.4％,以现有的技术水平和不变的投入要素,如果消除技术效率损失达到前沿生产面,农业生产总值还可以增加55.22％,提升的空间还很大;进一步分析出地方财政支农支出对农业发展有明显的推动作用,地方财政支农支出对农业技术效率的弹性系数为0.272,即地方财政支农支出每增加1％,农业技术效率增加27.2％,增加地方财政支农支出可提高农业技术效率;同时中国农业技术效率与经济地理条件相关性很大,农业技术效率因区域差别.呈现出显著性差异,经济发达地区农业技术效率显著高于经济落后地区,其中东部地区农业技术效率远高于全国水平及中西部地区.为缩小区域间农业技术效率差距,建议各地政府应适当调整财政支农支出水平,提高中西部地方财政农业科技支出.     

ON ESTIMATING ALLOCATIVE EFFICIENCY IN CROSS-SECTIONAL ANALYSIS OF PRODUCTION

In a recent reappraisal of evidence adduced for allocative efficiency in traditional agriculture, Dillon and Anderson employed a method based on a combination of traditional economic aspects and statistical aspects of estimated production functions. However, their reappraisal involved using marginal rather than the (appropriate) joint distributions of the regression coefficients. This paper investigates the error associated with using the inappropriate marginal distribution in a reassessment of allocative efficiency in wool growing in the Australian pastoral zone.     

中国西瓜产业生产效率的实证分析

中国是世界上最大的西瓜生产国,西瓜生产效率对西瓜产业的健康持续发展具有重要作用。研究通过追踪调查,收集了2010~2012年中国18个西瓜主产省市区生产成本收益的一手数据,并运用数据包络分析法（DEA）对西瓜生产效率进行了测算和分析。结果表明：从总体上看,吉林、辽宁、湖北、甘肃、湖南、河南和山东7省份西瓜生产效率达到DEA有效;从时间变动趋势来看, 2010~2012这3年间我国西瓜全要素生产率年均增长率为-28%,进一步分解得知主要是由于较大幅度的技术退步抵消了综合效率的促进作用,不同省域间西瓜全要素生产率增长率及增长方式也存在较大差异;从截面数据来看, 2012年我国西瓜生产的平均综合效率为0939,投入要素的使用效率整体较为合理,但仍存在投入冗余的状况,主要表现在农药和农膜的过度使用,并对生产技术无效率的省市区提供相应的效率改进方案。最后有针对性提出了提高我国西瓜产业生产效率的合理性建议。     

"生态移民"政策对缓解草原生态压力的有效性分析

内蒙古自治区阿拉善盟正遭受沙漠化的危害,过牧是导致沙漠化的主要原因,为解决此问题。已开始实施“生态移民”是一系列的战略措施;从野外考察和理论分析的结果来看,“生态移民”战略有可能产生意想不到的结果,不仅没有有效地缓解草原的生态压力,还可能导致过度开采绿洲有限的水资源;减轻草地生态压力的根本战略措施应该是提高牧民和相关人员保护草原的意识,加强群众不断从实践中学习的能力,探索改进草原的管理模式,促进牧区的可持续发展。“生态移民”只能位于辅助政策的地位。     

A NOTE ON HIDDEN GAINS AND LOSSES OF BUFFER STOCK SCHEMES FOR WOOL

This note is concerned with one aspect of the methodology for examining the gains and losses of a buffer stock scheme for wool. It is shown that it is incorrect to debit interest due on capital tied up in stocks of wool without, at the same time, crediting a portion of this to the grower. The errors that can occur in calculations that do not take account of the charged time distribution of growers' receipts are demonstrated.     

基于超效率DEA模型的中国农业科技资源配置效率动态演化研究

[目的]通过测算中国农业科技资源配置效率,分析存在的差异性,为配置效率的提升寻求有效措施。[方法]运用超效率DEA,对2001~2014年间中国31个区域的面板数据进行农业科技资源配置效率的全面评估,从中探究区域农业科技资源配置效率的变动趋势和时空特征,构建Malmquist指数以从技术进步水平和技术效率水平考察影响区域农业科技资源配置效率变动的因素。[结果]中国各地区整体的配置效率呈现上升趋势,超效率平均值从2001年的0.520上升到2014年的0.764;农业全要素生产率平均增长1.3%,其中综合技术效率指数年均增长4.2%、技术进步变化指数年均下降2.8%;从影响农业科技资源配置效率的技术进步和技术效率来看,技术效率已成为主要因素。从细分的6个区域来看,华东地区全要素生产率平均值最高,西北地区最低。从具体省份情况来看,有17个省(市、区)的全要素生产率指数大于1,其中天津、上海、广东、海南全要素生产率增长较快,年均增长率达到10%以上。[结论]提高中国农业科技资源配置效率,可采取优化农业科技资源配置结构,各地根据农业科技资源实际扬长避短、合作共赢,实施农业科技"走出去"战略等措施。     

A NOTE ON THE USE OF A MODIFIED INPUT-OUTPUT MULTIPLIER FOR LAND USE EVALUATION*

The modified input-output multiplier is proposed. Some limitations of the multiplier and the results of its application to four major land use industries are discussed.     

加入WTO后河北农业资源利用态势及效率分析

[目的]选择"加入WTO后河北农业资源利用态势及效率分析"为题,意在进一步合理利用农业资源,提高资源利用效率。[方法]以河北省农业资源系统为研究对象,采用比值分析和历史比较分析相结合的方法,对2001~2015年的河北农业资源利用态势及耕地资源、水资源以及化肥资源等主要农业资源的利用效率进行分析评价。[结果](1)从2001年底加入WTO到2015年的14年间,河北省耕地面积和作物播种面积都有不同程度减少,但粮食总产量基本保持增长态势,种植业产值更是大幅增长;耕地资源利用效率逐年提高。(2)农业用水量和农田灌溉用水量基本上都呈逐年下降态势,水资源利用效率持续提高。(3)化肥施用总量逐年增长,在化肥施用结构中,氮肥和磷肥所占比例逐年减小,钾肥和复合肥所占比例逐年提升;化肥利用效率逐年提高。[结论]2001~2015年,河北省农业资源利用效率持续提高,农业资源利用呈现出"资源节约,效率提高"的运行态势。但河北省农业资源禀赋有限,珍惜并保护好耕地资源,合理利用水资源,控制并科学施用化肥,仍将是保障河北农业和社会经济可持续发展的长期主题。     

海安县紫菜商会的经济效率分析

本文首先介绍了海安县紫菜业的发展状况和紫菜商会的基本情况,然后以经济学模型分析了紫菜商会的成立对紫菜养殖者利润的影响,指出商会的成立有利于提高养殖者的谈判力、有利于节约其交易成本,有利于提高其经济福利,因此建议有关部门应当适当引导(而不是强制)渔民建立协会,以便保护渔民利益.     

A NOTE ON VICTORIAN WHEAT YIELD DISTRIBUTIONS

An analysis of wheat yield series from ten localities in Victoria was undertaken to investigate for independence of observations and to test for normality of the distributions. The conclusion was reached that Victorian wheat yield series are composed of random observations and form frequency distributions which display slight negative skewness. The situation may be different for other crops or for wheat in other areas.     

东北地区耕地利用效率时空差异及其影响因素分析

[目的]对东北地区36个市(州)2005~2014年耕地利用效率进行测度,分析其时空差异,并找出耕地利用效率的影响因素。[方法]利用数据包络分析(DEA)方法计算得出各年各地区效率值,并利用Tobit回归模型其影响因素。[结果]2005~2014年东北地区耕地利用效率相对较高,规模效率值较为稳定,纯技术效率值波动上升,纯技术效率始终是影响综合效率的主要原因;黑龙江省的综合效率水平高于吉林省与辽宁省;在分解效率方面,黑龙江省的纯技术效率水平高于吉林省与辽宁省,吉林省的规模效率高于黑龙江省与辽宁省;受区域农业发展水平影响,不同地区农业投入的资源水平存在差异,综合效率、纯技术效率和规模效率均呈现出由黑龙江省向吉林省、辽宁省扩张的空间格局;从影响因素来看,受灾面积占农作物播种面积比重、单位耕地面积农用机械总动力、单位耕地面积施肥量、农村劳动力人均播种面积共同作用于东北地区耕地利用效率。[结论]东北地区耕地利用效率时空差异明显,多种因素共同影响地区耕地利用效率。