GOAL PROGRAMMING AND MULTIPLE CRITERIA DECISION-MAKING IN FARM PLANNING: SOME EXTENSIONS

This paper is the sequel to a previous article by Romero and Rehman on the role of multiple criteria decision-making (MCDM) techniques, particularly goal programming (GP), in farm planning. This assessment of the potential usefulness of the MCDM paradigm is carried further and now covers the extensions to GP and other related methodologies such as multiobjective programming, compromise programming, multigoal programming and generalised GP. Later analysis is focused on methods of dealing with uncertainty and risk in farm planning models, by demonstrating how game theoretic principles and the MOTAD approach (along with its main variant, target MOTAD) can be incorporated within the MCDM framework.     

A LINEAR PROGRAMMING SOLUTION TO SOME MARKET ALLOCATION PROBLEMS

Certain market allocation problems involving linear average net revenue functions can be solved by linear programming. The technique can be applied to an objective function derived from linear marginal net revenue functions, the objective being to force each marginal net revenue as near to zero as possible given the constraint set. If a particular problem is suited to a linear programming solution, researchers may prefer to use this technique rather than more sophisticated optimization methods.     

SHORT-AND LONG-RUN FARM PLANNING UNDER UNCERTAINTY; INTEGRATION OF LINEAR PROGRAMMING AND DECISION TREE ANALYSIS

The paper presents an approach to an integrated long-run and short-run farm planning under uncertainty, based on a decomposition of the problem into (i) a series of short-run plans, and (ii) a master long-run plan. The series of the short-run plans are parametrically solved by linear programming "variable right hand" techniques and are later integrated into a long-run program using a (computerized) decision tree analysis. The attitude towards risk of the farm operator is expressed in the willingness to maximize the expected value of the income stream over the planning horizon subject to the restriction that alternatives which may lead to lack of liquidity must be eliminated.
Ce travail présenle une approche tentative ďintégrer, sous conditions incertaines, une planification de ferme à court et long terme. La planification est basée sur la partition du problème en (i) série de courte durée et (ii) de tongue durée. Les séries de courte durée sont résolues àľaide dun programme linéaire, et intégreés ensuite dans un programme à long terme àľaide de ľanalyse de "décision arbre."ľattitude envers les risques de ľentrepreneur est exprimée par la volonté-de maxiliser la valeur de revenu prévu au delá de la planification sous resérve de la restriction que des alternatives qui peuvent conduire à un manque de moyens liquides, doivent être éliminees.     

THE INFLUENCE OF WORKING CAPITAL ON FARM ORGANIZATION — HOW APPROPRIATE IS A LINEAR PROGRAMMING ANALYSIS?*

Effective limitations on farm working capital are not easily identified but behaviour consistent with such limitations is observed. Using a linear programming analysis, the results of having limited working capital are shown. It is also shown that the value of the working capital resource is so high that farmers make every endeavour to keep it free from limitation.     

PROFIT MAXIMISATION AND IMPERFECT COMPETITION—AN APPLICATION OF QUADRATIC PROGRAMMING TO HORTICULTURE*

This paper discusses the determination of profit-maximising behaviour under conditions of imperfect competition in product and/or factor markets. After stating a quadratic programming model which restricts product demand and factor supply functions to a linear form, an empirical application to a New Zealand nursery firm is discussed. It is concluded that such quadratic programming models should have an important role to play in horticultural management     

EXPERIENCES WITH FARMER ORIENTED LINEAR PROGRAMMING FOR CROP PLANNING

This paper presents a linear programming model for farm planning known as the "Purdue Top Farmer Cropping Model 'B'." This model is designed for direct use with farmers and has been used by more than 5,000 individuals. The paper describes the features of this model and discusses the rationale for these features. In this process details on application, evolution and impact of the model are given. The success of the model is due to its design and the interplay between research and extension personnel in the model design.
Un modèle de programmation linéaire, connu sous le nom de "Purdue Top Farmer Cropping Model 'B'," et destiné à la planification de la production des exploitations agricoles, est presenté dans ce rapport. Le modèle, déjà employé par plus de 5000 individus, est construit de manière à être directement utilisable par les exploitants agricoles. Le rapport décrit et expose la raison d'être des caractéristiques du modèle. Des détails sur les applications, l'évolution et l'impact de ce dernier sont fournis. La collaboration entre Je personel de recherche et d'extension dans le dessin du modèle en explique le succès.     

IMPLICATIONS OF AGGREGATION BIAS FOR THE CONSTRUCTION OF STATIC AND DYNAMIC LINEAR PROGRAMMING SUPPLY MODELS*

Aggregation bias is acknowledged to be one of the more serious problems confronting the Linear Programming approach to supply analysis. Whilst the literature abounds with theoretical solutions to the problem there is a notable lack of ideas on how these solutions might be made operational. This conclusion holds a fortiori for the dynamic case. This paper discusses a practical methodology for the classification of farms in order to minimise aggregation bias, and also the implications of avoiding bias for the specification of dynamic linear models.     

LINEAR PROGRAMMING MODELS FOR DETERMINING IRRIGATION DEMAND FOR WATER*

The purpose of the paper is to discuss linear programming models useful in estimating irrigation demand for water. The discussion is limited to technique and first reviews the general characteristics of linear programming models. The author then goes on to indicate the results of several models developed at the University of Manitoba to estimate irrigation demand. Cet article a pour dessein de discuter des modèles de programmation linéaire qui seraient utiles pour eslimer la demande ?eau pour ?irrigation. La discussion est limitée a la méthode à suivre et revolt en lout premier lieu les caractéristiques généraux des modèles de programmation lineaire. Linéaire continue alors avec une analyse des résultats de plusieurs modèles pour eslimer la demande ?eau pour ?irrigation développés à?Université Manitoba.     

LABOUR ON THE FAMILY FARM: A THEORY AND SOME POLICY IMPLICATIONS

This paper seeks to examine the labour-input decisions on family farms at a theoretical level and to demonstrate some policy implications of this theory. Where the family has the opportunity to work on the land, utility maximisation, rather than profit maximisation, would seem to be a more appropriate criterion for decision-making. Accordingly, the decision-making process is analysed under this alternative assumption. We then consider some of the policy implications of this model. In particular, we consider the effects of policies on the labour-inputs since the optimal allocation of labour is at the heart of most agricultural policies.     

A LINEAR PROGRAMMING STUDY OF FAMILY-RUN DAIRY FARMS IN NORTHERN IRELAND

The paper presents the results of a study in which multiperiod linear programming models were used to examine the probable responses of small and medium sized dairy farms in Northern Ireland to various policy, farm indebtedness and development options and to project consequent structural change in the dairy sector. The introduction of quotas has curtailed the considerable potential for expansion of output on these farms while having a less detrimental effect on farm profits and the survival of the smaller dairy herd than the price cut necessary to produce the same reduction in output.     

AN ALTERNATIVE SOLUTION TO LINEAR PROGRAMMING PROBLEMS WITH STOCHASTIC INPUT-OUTPUT COEFFICIENTS

Deriving acceptable farm plans where input-output coefficients are stochastic is a complex problem. Previous formulations have required many simplifying assumptions about the stochastic variables in the analysis. This paper presents an alternative approach based on the mean absolute deviation, which permits solution by a conventional linear programming algorithm whilst avoiding some of those assumptions previously required. The formulation also incorporates a stochastic objective function. Examples are provided using the situation of stochastic feed supply with reference to representative sheep-grain farms on the Northern Tablelands of New South Wales. Results from these suggest that this alternative approach is a distinct improvement on earlier stochastic formulations which utilize linear programming algorithms.     

A MIXED INTEGER LINEAR PROGRAMMING EVALUATION OF SALINITY AND WATERLOGGING CONTROL OPTIONS IN THE MURRAY-DARLING BASIN OF AUSTRALIA

Pollution of the River Murray by salt imposes costs on domestic and industrial users in Adelaide and to irrigators on the River Murray. Salt enters the Murray-Darling system through saline ground water aquifers and from irrigation and drainage of saline land. Irrigation and drainage generate benefits from improved agricultural productivity and impose costs through increased salt loads to the Murray-Darling system. The salinity of the River Murray can be reduced by pumping highly saline ground water into evaporation basins before it enters the River Murray. This paper presents a mixed integer linear programming model which is used to determine the mix of ground water interception schemes and land improvement schemes that minimises the net present value (over a time horizon of 30 years) of total Murray-Darling Basin costs due to salinity and waterlogging. By varying a target salinity level, the mix of works that yields various salinity targets in the River Murray at minimum cost is obtained. The sensitivity of the optimal solution to prescribed changes in costs and benefits of projects and to a longer planning horizon is examined.