ESTIMATION OF BENEFITS FROM DEER AND MOOSE HUNTING IN MANITOBA

Wildlife production has been suggested as a socially beneficial alternative to agriculture on marginal land. Since most wildlife species are fugitive common property resources, the private sector is assumed to be incapable of generating optimum outputs. Therefore, public investments in habitat and game protection and management are assumed to be beneficial, provided that funds are appropriately allocated. Criteria are needed for optimizing such public investments, and the benefit cost approach is currently used. Benefit evaluation is one important aspect of this approach. In the present study the benefits of deer and moose hunting in a selected area of Manitoba have been estimated and projections made for 1975 and 1980. The benefit calculations are based on estimated demands for hunting, using a model in which distance and hunting site quality are independent variables. The demand and benefit estimates will be of interest to land use planners and wildlife managers. Data used in the study were obtained from surveys by the Manitoba Wildlife Branch and the Department of Agricultural Economics, University of Manitoba II a été suggéré que la production du gibier serait une alternative qui apporterait des bénéfices sociaux où?on pratique ?agriculture à terres marginales. Elant donné que la plupart des espèces sauvages sont de caraclère fugilif ainsi qu'une proprieté commune, nous croyons qu'il est impossible pour le secleur privé de produire un rendement optimal. Par consequant, nous présumons que des investissements publics trail à la protection et la gestion du gibier et de son habitat offrenl des avantages, pourvu que les fonds soienl correctement distribués. On a besoin de critères pour optimaliser de tels investissements publics, et la méthode “benefit-cost” est ?usage couranl. ?évaluation des bénéfices est un aspect important de cette méthode. Dans la presente étude les bénéfices de la chasse aux chevreuils et aux orignaux dans une région sélectionnée du Manitoba ont été estimés et des projections onl été effectuées pour les années 1975 et 1980. Les calculs des bénéfices onl pour base des estimations des demandes pour la chasse, à parlir ?un modèle dans lequel les variables indépendantes sont la distance et la qualite des endroits de chasse. Les estimations des demandes el des benefices seront intérèssantes aux planificaieurs de ?utilisalion des terres et aux direcleurs de ?enlretien des terrains de chasse. Les données utilisées dans cette étude ont été oblenu à partir de questionnaires utilisés dans des enquêles menées par la Division de Chasse et Pêche du Manitoba et par le Département ?Economie Rurale de ?Université du Manitoba     

METHODS OF ASSESSING AGRICULTURAL DEMAND FOR WATER IN THE PRAIRIES*

It is vital that policy makers have good evluations of society's needs for water development and regulations. However, in order to make valid normative assessments, there must first be more adequate forecasts of attainable water use patterns. Conditional forecasting is suggested as being most appropriate. In this paper an outline of factors affecting agricultural water use is provided. A discussion is given of three approachs to conditional forecasting: extrapolation of production requirements, fitting production functions by regression, and programming. Advantages and disadvantages of each are discussed with attention to methodological details. Precautions are outlined for aggregation procedures and the evaluation of results. Recommendations are made on some basic issues affecting water researchers, and an attempt is made to identify iterhs needing priority attention. II est, essentiel que les planificateurs s'occupant de ?aménagement el de la règlementation d, es eaux aient unc bonne évaluation des besoins de la société. Cependant, afin de produire des évaluations valables nous devons avant tout oblenir des prévisions adèquales des systèmes accessibles de ?ulilisation des eaux. Les prévisions conditioners sont suggéreés comme étant les plus appropriées. Dans cetie étude, nous fournisons les données générates sur les différents facteurs affectant Ǐulilisation des eaux en agriculture. Ensuite, nous donnons une discussion de trois méthodes sur la calculation des pronostics condilionnels, lesquelles sont ?extrapolation des exigences de la production par régression el la programmation. Les avantages el désavantages de chaque méthode sont discutées avec attention aux détails méthodologiques. Des mises en garde sont données sur les procéd is ?assemblages el de ?évaluation des résultats. De plus, des recommandalions sont faites sur des issues fondamenlales qui affectent les chercheurs dans le domaine de ǐutilisation des eaux et un effort est fourni afin ?identifier les details demandant une attention prioritaire.     

MEASUREMENT OF FIRM-SPECIFIC TECHNICAL EFFICIENCY: A COMPARISON OF METHODS

Various procedures have been used for the measurement of firm-specific technical efficiency. Most commonly used methods are static and deterministic. Deterministic methods tend to yield biased estimates of technical efficiency and to overestimate the variability of technical efficiency over time. These conclusions are illustrated by applying stochastic frontier production function analysis and corrected ordinary least squares procedures to farm data from Sri Lanka.     

粮食产量空间化中4种误差修正方法的对比与分析

[目的]空间化作为一种常用的地学数据处理方法,必然会存在一定的误差,而对空间化结果进行误差修正,可以降低空间化误差。[方法]文章以2005年粮食产量空间化为例,以各地市不同农田类型(水田、水浇地、旱地)面积数据为自变量,以各地市粮食产量统计数据为因变量,进行多元线性回归分析建模。在具体建模时,令常数项为0,将全国分为7个区,各区分别建立回归方程。然后分别利用4种误差修正方法对空间化初步结果进行修正。选取4种误差评价因子,对修正前后的空间化结果的精度进行对比和分析。[结果](1)均值法不能被用于修正空间化初步结果;(2)比例系数法、权重系数法Ⅰ(不同农田类型同一权重)和权重系数法Ⅱ(不同农田类型不同权重)3种方法都可以被用于修正空间化初步结果;(3)利用权重系数法Ⅰ修正后的空间化结果的精度最高,比例系数法次之,权重系数法Ⅱ最差。[结论]误差修正方法对提高空间化精度具有重要影响。该研究虽以粮食产量空间化为例,但所得结论同样适用于其他社会经济统计数据的空间化研究,对以后统计型数据空间化研究具有一定的参考价值和指导作用。     

TECHNICAL EFFICIENCY: A COMPARISON OF PRODUCTION FRONTIER METHODS

Recent differences in the measurement of farm efficiency may be related to the methods employed. Here, four alternative production frontiers are estimated using time-series, cross-section data for a sample of Illinois grain farms. Efficiency measures are found to be highly correlated between nonparametric methods, and between parametric methods. However, large differences are noted when efficiency measures are compared between nonparametric and parametric methods. An analysis of farms with large differences, which are efficient under the nonparametric method, indicates that correlations between efficiency measures are much higher when these firms are excluded.     

时间序列植被指数重构方法比对研究

时间序列植被指数在植被遥感监测中发挥着重要的作用,但其往往存在大量噪声影响,在应用之前需要进行时序植被指数重构。耕地植被指数是进行农作物长势监测与估产以及农业生态系统对气候变化响应等研究的重要工具,本研究借助MODIS植被指数产品,以东北三省耕地为研究区域,针对非对称高斯函数拟合（AG）、双Logistic函数拟合（DL）和Savitzky-Golay滤波（SG）三种常见的时序植被指数重构方法,从原始数据质量对时间序列植被指数重构的影响、不同重构方法对原始数据的保真性和基于不同重构方法的耕地生长季长度空间格局等方面进行了对比分析。首先对NDVI及其质量控制数据进行分析,探讨原始数据质量对时序植被指数重构的影响;然后选择若干随机抽样点,从定性和定量两个角度来评价不同方法对时序植被指数的重构效果;最后借助研究区的耕地物候特征,间接对不同的时序植被指数重构方法进行对比。结果表明,在东北三省利用这三种方法进行耕地时序植被指数重构时需要引入质量控制数据,AG拟合和DL拟合在该地区耕地时序植被指数重构时表现相似且比SG滤波更加适宜。     

A COMPARISON OF TOBIT AND OLS ESTIMATES OF JAPANESE PEANUT IMPORT DEMAND

A Tobit analysis is applied to estimate Japanese peanut imports under quota restrictions for the period 1973–1988, and to assess the bias when the presence of quota is ignored by using OLS estimation. The results show that biased estimates are obtained by using OLS in the presence of quota restrictions.     

A COMPARISON OF DEPRECIATION METHODS UNDER CURRENT COST ACCOUNTING

In New Zealand the Richardson Report has recommended to government the adoption of a form of inflation accounting known as Current Cost Accounting (CCA). This paper reports research carried out to determine which of the traditional historical cost depreciation methods used in farm accounting might be most appropriate when adapted to a current cost basis. The current cost depreciation methods are compared on the basis of their ability to predict accurately actual replacement values for a survey sample of farm tractors and headers. The resultant measures of depreciation are compared with those currently allowable under New Zealand taxation laws, and the proposition that investment allowances on purchases of new machinery offset the inadequacies of historical cost depreciation is discussed.     

粮食需求预测方法述评

在国内外24篇有代表性的粮食需求预测文献基础上,文章重点对这些文献的预测时间、预测结果、预测方法、预测的地区、城乡和品种差异进行了比较分析.现有文献的3个主要特点是:首先,定性分析、时间序列模型和联立方程模型是最常见的三种方法,单方程模型和其他方法应用较少;第二,文献集中关注2010 ～2030的粮食需求预测,且在相同时间点不同文献的预测结果比较接近;第三,在预测中,少数文献关注地区差异、城乡差异或品种差异,并且同时关注3种差异的只有1篇.在对现有文献评价基础上,文章提出粮食需求预测领域应进一步深入研究的方向.     

A COMPARISON OF RISK EFFICIENCY CRITERIA IN EVALUATING GROUNDNUT PERFORMANCE IN DROUGHT-PRONE AREAS

This paper contributes to an evaluation of the performance of ground nuts in drought-prone areas by estimating yield response functions to water from experimental data. They are combined with meteorological data to simulate yields by location. Efficient genotypes are identified by several risk criteria. Genotype rankings based on these risk criteria and simulated yields are different from those based on experimental data and plant scientists' traditional methods of evaluation.     

A MODEL OF THE DISAGGREGATED DEMAND FOR MEAT IN AUSTRALIA

The focus of this study is the estimation of the Australian demand for meat between 1967 and 1990, employing a demand systems approach which uses the linear approximate, almost ideal demand system (LA/AIDS) model. Two demand systems are estimated by maximum likelihood methods, one for aggregate types of meat and one for disaggregated meat products. After correcting for serial correlation in the two demand systems, restrictions from utility theory are imposed and tested for their appropriateness. By using a new data set on the Australian retail price and consumption offresh pork, ham and bacon, the results from the disaggregated model provide the first estimates of the own-price, cross-price and expenditure elasticities for these commodities.     

ANALYSIS OF EXPORT DEMAND FOR CANADIAN WHEAT

The objectives of this study are to identify the main factors affecting foreign countries' imports of wheat, and to interpret the implications for Candian wheat export policy. Analyses have been made if import demands of twelve countries, including four which have purchased approximately 60 percent of Canadian wheat exports during the last five years. The study focuses on methods of estimating the price elasticity of demand in the purchase of wheat by individual countries. Three models were applied: the direct, the substitution, and the market share model. The substitution model performed best and was judged to have the greatest potential for further research. Significant negative price elasticities considerably greater than unity (in absolute terms) were found for several countries, including some major importers. This suggests that there are large potential gains obtainable for Canada by decreasing price. However, unless the Wheat Board adopts multiple pricing, these gains would be at least partly offset by losses in markets which appear to be much less responsive to price. L'objectif de cette étude est ?identifier les principaux facteurs qui affectent les importations de blé aux pays étrangers et ?évaluer la portée de ses facteurs sur la politique canadienne ?exportalion du blé. On a analysé les demandes ?importation de 12 pays, dont quatre ont acheté prés de 60 pourcent des exportations canadiennes de blé au cours des cinq dernières années. Cette etude se concentre sur les méthodes ?estimation de I‘élasticite de demande des pays individuels. On a utilise trois modèles dit: “direct”, “substitution”, et “le portage du marché.” Le modèle “substitution” donna les meilleurs résultats et semble le plus prometteur pour de telles recherches dans I'avenir. Des élasticites négatives et significatives de prix, plus grand que ?unité (en termes absolus) ont été obtenues pour plusieurs pays incluant quelques-uns des plus gros importateurs. Ceci nous laisse croire qu'il y aurait des possibilityée de gains accrues si le Canada réduisait ses prix. Cependant, à moins que la Commission Canadienne du Blué n'adopte une systeme de prix différentiels, ces gains seraient au moins particllemcnt réduits par des pcrtes dans ?autres marchés qui paraissent être moins sensibles aux changements des prix.     

THE ELASTICITY OF DEMAND FOR THE EXPORTS OF A SINGLE COUNTRY — A RECONSIDERATION

One country's exports of a particular commodity are usually imperfect substitutes for similar exports from other countries. Consequently, the price elasticity of export demand involves unknown cross elasticities between sub-groups of the commodity. However, there are constraints on the relative magnitudes of all the sub-group elasticities. These make it possible to assess the degree to which the whole commodity elasticity divided by the market share is an over-estimate of the export elasticity.     

A COMPARISON OF INCOME AVERAGING PROCEDURES FOR INCOME TAX PURPOSES

A comparison is made of a number of income averaging procedures on the basis of selected performance criteria. The main conclusion which emerges is that the Australian income averaging procedure, currently applied to primary producers, has a number of defects. Several of the alternative income averaging procedures reviewed are judged to be superior to the current Australian system.     

论市场经济对财务专家的要求

现代市场经济条件下财务专家应具备高超的智能素质,全面的理财知识和卓越的工作才能.文章从基本素质、市场经济观念、理财原则三个方面论述了市场经济对财务专家的要求.