PREMIUM RATEMAKING IN AN ALL RISK CROP INSURANCE PROGRAM1

Fluctuation in farm incomes resulting from variation in crop yield is one of the most significant features in agriculture. Crop insurance is a feasible method by which the farmer can protect his income and his investment from the disastrous effects of crop losses due to natural hazards. This study has attempted to cover two parts. First, it has examined the most important-factors influencing crop yields in connection with the premium rate scheme (i.e. the long-run average yield and the level of coverage). These factors include resource inputs, technology, weather, and stochastic variable. Second, it has developed a refined method of approximating the premium rate. The data used in testing normality were based on the Manitoba Crop Insurance Corporation's annual yield survey covering the years 1916 to 1964. The test shows that none of the annual yield distributions within the area surveyed was normally distributed, revealing that a cartful and exact delineation of a crop risk area is necessary. The findings also show that the cyclical pattern of weather and the upward trend in crop production due to technology were evidently important for the adjustment of the level of coverage and premium rate over time. Additional research relating the effects of weather and technology on crop yields would help to establish a more realistic insurance program. Other aspects should not be overlooked. These include (a) other possible levels besides the existing level of coverage and (b) a livestock or a combined crop-livestock insurance program along with the crop insurance program. The purpose of these additional aspects is to provide farmers with a fuller measure of protection.     

MALLEE WHEAT FARMERS' DEMAND FOR CROP AND RAINFALL INSURANCE

Producers' demand for a crop insurance program with indemnities based on their actual yields and a rainfall insurance program with indemnities based on area rainfall is analysed. Actuarial costs of these hypothetical programs are estimated. Tobit procedures are used to analyse factors influencing the amount which farmers would be willing to pay for the alternative insurance programs. Factors related to the absolute size of risk and capacity to bear risk, as well as personal characteristics and risk attitudes of producers, have effects on the demand for insurance as hypothesised. Problems of adverse selection are associated with the area yield-based program, while both crop and rainfall insurance programs may involve some moral hazard. Producer participation in either program would be limited.     

AN ANALYSIS OF PEASANT FARM PRODUCTION UNDER CONDITIONS OF UNCERTAINTY*

In this paper the impact of cotton on a traditional food crop system in a semi-arid area of Kenya is analysed using a linear programming model and sensitivity analysis. Alternative criteria, maximax, maximin, and a standard average return maximand, are used in turn. The solutions are all evaluated as ‘best year’, ‘worst year’, and average values. This gives a range of results that cakes account of the uncertainty in the farming situation. Several policy conclusions follow from the analysis. It is argued that the approach used is more realistic than an approach in which a single maximand is used, and that the simplicity of the approach brings it within reach of many involved in farm production analysis.     

农作物秸秆肥料化利用研究文献计量分析

[目的]对国内外的秸秆肥料化利用研究现状、研究热点和发展趋势进行整体分析,总结秸秆肥料化领域中存在的主要问题,为今后我国秸秆肥料化利用提供参考和建议。[方法]文章基于Web of Science核心合集数据库和中国科学引文数据库,采用Gephi软件对文献进行可视化计量分析,主要对1999—2019年国内外有关秸秆肥料化利用领域的国内外研究力量、研究热点以及研究趋势进行分析。[结果]（1）2006年以后外文文献呈快速增长趋势,而2016年以后中文文献进入基本稳定阶段。（2）外文文献发表数量最多的研究机构依次为中国科学院、美国农业部农业研究中心和加拿大农业与农业食品部;中文文献数量最多的研究机构依次是西北农林科技大学、南京农业大学和甘肃农业大学。（3）外文文献发表数量排名前三的期刊分别是Soil and Tillage Research、Soil Biology and Biochemistry、Agronomy Journal,其中Soil Biology and Biochemistry单篇平均被引频次最高（52.5次/篇）;中文文献发表数量排名前三的期刊分别为《农业工程学报》《农业环...     

AN ANALYSIS OF MULTIOBJECTIVE DECISION-MAKING FOR THE SCOTTISH INSHORE FISHERY

The Scottish inshore fishery is used to illustrate the application of a multiobjective analytical model to decision-making for fisheries management. Although the quantitative analysis is necessarily fishery-specific, much of the discussion is of more general applicability. A hybrid modelling approach is used to analyse fisheries management objectives for this fishery: regression-based models of the fishing process are used to provide input into linear and goal programming models, the linear programme also providing input into the goal programme. Optimisation of the goal programming model results in an ‘optimal’ pattern of resource allocation for the Scottish inshore fishery.     

MEASURING THE EFFECT OF WEATHER ON CROP PRODUCTIO*

Farm income is greatly affected by the impact of weather on crop production. Relating crop production to weather requires an index that is relatively specific to a local area. A single index is preferable in economic analysis to avoid including many weather variables that may be highly intercorrelated and to preserve degrees of freedom for testing the models chosen. The unique feature of the reported index is the use of readily available data and the direct estimation of the effect of weather on yield per acre. The resulting weather index was found to be reasonably accurate, and thus suitable for use in studies concerned with such diverse topics as the benefits of environmental control and the stability of farm income.
WE ANALYSE DBS CONDITIONS CLIMATIQUES SUR LE RENDEMENT DES CULTURES. — Le revenu agricole est grandement affectée par les conditions climatiques sur le rendement des récoltes. Le rapport entre les deux demande un indice qui relate particulièrement à une région précise. Un seul indice est preferable dans l'analyse économique afin d'éviter d'y inclure trop de variables qui pourraient être et de préserver un dégré de liberté dans l'application des modèles choisis. L'unique caractéristique de cet indice est l'emploie des données disponibles et une évaluation juste des conditions climatiques sur le rendement à l'acre des cultures. Les résultats sur l'indice des conditions climatiques semblent être très efficace, ainsi convenable à l'usage des études concernant les avantages d'un contrôle de milieu et de la stabilité du revenue agricole.     

LONG SWING HYPOTHESIS FOR CATTLE AND HOG OUTPUT AND PRICES IN CANADA: AN APPLICATION OF SPECTRAL ANALYSIS*

Knowledge of the nature of variability in the cattle and hog sectors of Canadian agriculture may be considered an aid in developing effective stabilization policies for agriculture. Traditional times series methods have been applied in the past to ascertain the nature of cyclical fluctuations in cattle and hog sectors. In this paper an attempt is made to ascertain the cattle and hog cycle using the concept of spectrum. Monthly data for the period January 1949 to April 1972 were employed. In addition, for the cattle sector annual observations for the 1914–1972 period were used to verify the existence of long swings. A preliminary analysis of monthly data revealed the presence of serious seasonal fluctuations in data, which were subsequently removed using a time-invariant linear filter. The study suggests the existence of a 40-month cycle in hog output and a 10-year cycle for cattle. The study further tested the existence of these cycles by varying the number of truncation points. The length of the dominant cycle remained unchanged with the change in the number of truncation points. Une connaissance de l'espèce de variabilité qui existe dans le domaine des bodives et des cochons dans l'agriculture canadienne peut être considérée avantageuse an développement des mésures efficaces pour la stabilisation de l'agri-culture. On a employé au passé, les méthodes traditionnelles des séries de temps pour déterminer la nature des fluctuations cycliques dans le domaine des bodives et des cochons. Dans cet ouvrageci, on a essayé de déterminer le cycle des bodives et des cochons en se servant du concept des spectres. On a fait usage des données mensuelles pour le période Janvier 1949 jusqu'à avril 1972. En outre, dans le domaine des bovins on a employé des observations annuelles pour la période 1914–1972 pour vérifier l'existence de grands changements temporels. Une analyse préliminaire des données mensuelles a révéle la presence des grandes fluctuations des données. On s'est débarrassé des ces fluctuations en employant un filtre linéaire de temps invariable. L'etude suggère I'existence d'un cycle de 40 mois dans la production des cochons et un cycle de 10 ans dans le cos des bovides. En outre, l'étude a examiné l'existence de ces cycles en variant le numéro des points de troncature. La longueur du cycle dominant est resté le même, malgré le changement dans le numéro des points de troncature.     

AN ECONOMETRIC ANALYSIS OF THE SUPPLY AND MARKETING OF APPLES IN NOVA SCOTIA*

The supply of apples in Nova Scotia is disaggregated in two dimensions: by variety–namely, fresh, processing, and dual purpose apples and by number of bearing trees and yield per tree. Using regression techniques, price distributed lags explained tree planting decisions. Market variables and climatic factors such as frost, sunshine, and wind explained yield. Simulation studies indicate (I) a relative stability in the population of apple trees, (2) a noticeable sensitivity of yield to climatic factors, especially wind in unfavorable cases and sunshine in favorable ones, and (3) that the buffering effect of dual purpose apples and the relative inelasticity of demand for processing apples both help maintain relative overall stability in the industry in the face of unpredictable climatic variations. On divisé?apprivisionmemenl des pommes de la Nouvelle Ecosse en deux: ?abord par varietés, la pomme de consommalion, la pomme industrielie, les pommes peuvent servir 1'un ou I'autre de ces fins et ensuiie par le nombre de pommiers et le rendement par arbre. Employant une technique regressive, ?on peut comprendre que le nombre de pommiers planter dépendent directement du prix des pommes sur le marché. Par variations dans le marché et les conditions climatiques telle que le gel, ?énsoleillement el le vent expliquent le rendement. Des études controlées nous indique: 1. Une stabilityé relative dans le nombre des pommiers 2. Une variation marquée suivant les conditions climatiques, spéciallemenl le vent, (condition infavourablejet lesoleil(conditionfavorable) 3. Que I'effet amortissônt des pommes a double fins et ?inélasticicité de la demande pour les pommes preparées a la consommalion aident à maintenir une certaine stabilityé dans cette Industrie aux prises avec les changements climatiques imprévisibles     

USUFRUCT AND USURY: AN ANALYSIS OF LAND LEASING IN EAST JAVA*

On Java, land leasing functions as a credit instrument when the entire rent is paid in advance. The rights obtained by the tenant/lender are the 'price' of the loan made to the land owner/borrower. A model of such transactions shows that the area leased and duration of the lease are substitutes in raising a loan of given size and that the substitution rate is related to the term structure of interest rates.     

种养结合经济效益剖析 ——山东省禹城市小付村农户调查报告

从禹城市小付村农户的三种农业生产方式看,"种养结合"的人均纯收益和成本收益率等项经济指标远高于单纯种植业或养殖业.从而说明种养结合生产方式是当地农户充分利用有限农业自然经济资源获取更多经济收入的有效途径.     

ESTIMATION OF EFFECTIVE RISK REDUCION THROUGH IRRIGATION OF A PERENIAL CROP*

This paper outlines an approach to assessing the benefits from in vestment in the irrigation of tea stands in three areas of East Pakistan. Irrigation aflects both the establishment and productive life of the growing crop, and therefore the analysis includes a discounred assessment of the replacement decision, as well as an appraisal of the change in technology. Since the biological and weather eflects that determine annual and long-run productivity of the stand are stochastic variables, the evaluation is made using a simulation model in which these determinants are introduced as known discrete probabilities. Using this model an estimate may be made of rhe net gains to a tea estate of the risk reduction achieved by eliminating harmful crop moisture deficits.     

THE DEMAND FOR MEAT — AN EXAMPLE OF AN INCOMPLETE COMMODITY DEMAND SYSTEM*

Equations describing the demand for beef and veal, mutton, lamb, pork and chicken are estimated using the full information maximum likelihood estimator. Elasticity estimates are presented and the double logarithmic model is compared with a demand system which is derived from the indirect translog utility function. Estimates of the direct price and income elasticities are not particularly sensitive to model specification but the estimated cross-price elasticities are sensitive to the choice of functional form. The results indicate that the double logarithmic specification may be less satisfactory than the alternative presented in cases where restrictions on the parameters are imposed during estimation.     

OPTIMAL FEEDING POLICIES FOR BROILER PRODUCTION: AN APPLICATION OF DYNAMIC PROGRAMMING*

The determination of an optimal feeding and selling strategy for broiler production given a space constraint is formulated as a dynamic programming problem. Production equations derived from trial data are used to obtain an optimal sequence of rations in which energy density changes through time. The stability of the plan is explored and the implications of the results for production research and commercial practice are considered.     

农作物种植适宜性评估系统的设计与实现

该文介绍了利用GIS平台的叠加分析和统计分析等功能所建立的农作物种植适宜性评估系统的设计思路、特点和功能,系统通过分析气候资源、土壤资源和地形条件对农作物种植适宜性的影响,建立评价和区划指标,提高了农作物引种栽培气候适宜性评估和农业气候区划的自动化水平。     

A MODEL OF JOB CHOICE FOR THE ANALYSIS OF GOVERNMENT INTERVENTION IN STRUCTURAL ADJUSTMENT*

The paper presents a model of choice between alternative available jobs in which each job has an uncertain multi-period income prospect. Imperfectly informed expectations as well as job preferences and attitudes to risk determine the choice. The model is used to locate and discuss some problems of designing government programs which are intended to increase job mobility. The main conclusion is that government interventions may impose costs on the economy which are greater than the benefits because the information needed to assess costs and benefits is not generally available and political pressures may distort the expenditures.     

“城居保”对中国农村家庭消费支出异质性实证研究

[目的]全面分析城乡居民基本养老保险制度对农村家庭各项消费支出现状的影响,就进一步完善该项政策和稳定农村消费市场提供重要的理论参考。[方法]文章以消费和储蓄生命周期理论为分析框架,通过选取合理的样本面板数据,运用系统GMM回归分析方法探究了城乡居民基本养老保险制度对农村家庭消费支出水平的影响。[结果]财产性收入是影响农民参与城乡居民基本养老保险制度的主要因素以及投保档次的制约因素,作以存量财富为基础的财产性收入要比流量形式存在的财富具有更强抵御风险的能力,即财产性收入在很大程度上可以增加农村家庭对养老保险的依赖程度。另外,城乡居民基本养老保险制度对农村家庭消费能力表现出异质性影响。其中,城乡居民基本养老保险制度对农村家庭生活消费支出、食品性等日常性支出、文体消费支出水平明显要高于对医疗消费支出水平。[结论]国家要加大宣传城乡居民基本养老保险制度的积极和辐射作用,让广大农村家庭能够真正了解这项政策的意图。同时,要逐步破解城乡二元结构等制度性障碍,让更多农村家庭能够享受到与城镇居民相同的养老待遇。