Calibration of agricultural risk programming models using positive mathematical programming

Mathematical programming models of farmers’ cropping decisions must first be calibrated before they can be used to examine agricultural producer responses to policy changes. In this paper, we compare three calibration approaches for disentangling the risk parameter from the parameters of the cost function: one assumes a logarithmic utility function, while the others employ an exponential utility function. Historical crop insurance data for southern Alberta, Canada, are used to assess the calibration performance of the three approaches, and sensitivity analysis is implemented to test whether the changes in the optimal land allocation caused by the changes in the values of the parameters are practically reasonable. Only one of the three models is of practical use for policy analysis because it can recover the true values of the parameters and the results of sensitivity analysis are reasonable.     

Area Allocation Under Price Uncertainty on Dutch Arable Farms

This paper uses a Mean-Variance utility function to build a dual model that simultaneously determines area allocation and production/input levels under output price uncertainty. Regularity conditions of the indirect utility function (convexity) and producers risk preferences are tested. The framework is applied to a rotating sample of Dutch arable farms. Dutch arable farmers are found to be risk averse, with the size of the risk premium given by 3 per cent of annual profit. A bootstrap resampling method shows that curvature conditions are rejected. Price elasticities are compared for an unrestricted model and for a model with curvature conditions being imposed.     

Estimating Intertemporal Preferences for Natural Resource Allocation

In this article, we show how the degree of risk aversion, discounting, and preference for intertemporal substitution for a natural resource manager can be structurally estimated within a recursive utility framework. We focus on the management of a reservoir in California, and test the data for consistency with a recursive utility model specification versus standard time-additive separability. The results show that the data are consistent with a risk-averse manager with recursive preferences. The data also reject time-additive separability, with or without risk aversion, such as the standard constant relative risk aversion utility model. The improvement in model fit when recursive preferences are used is notable.     

Specification and Estimation of Production Risk, Risk Preferences and Technical Efficiency

This article deals with specification and estimation of risk preferences, production risk, and technical inefficiency. It makes contribution in three separate areas of production economics. First, we model producers' attitude toward risk and derive risk preference functions (without assuming any parametric form of the utility function and any distribution of the error term representing production risk) when risk arises from production uncertainty and technical inefficiency. Second, the standard production risk model is extended to accommodate technical inefficiency and producers' attitude toward risk. Finally, the technical efficiency model is generalized to accommodate production risk and producers' attitude toward risk.     

Incorporating nutrients into meat demand analysis using household budgets data

The objective of this article is to analyze the Spanish demand for meat, taking into account the consumer's concern about the relationship between food diet and health. This concern is forcing food demand analysts to assume that consumer utility is a function of nutrients instead of simply the food products themselves. Nevertheless, these utility function arguments are not produced in the marketplace but rather at home. As a consequence, in this article household production theory is followed in order to analyze Spanish demand for meat using the Quarterly National Expenditure Survey for 1999. Demands for several meat products (the input in the model) are derived from the translog cost function. Censored regression models are used in the estimation process, since many zero responses are reported. Five broad categories, eight nutrients, and the most relevant socioeconomic variables are considered. Finally, a set of elasticities is calculated with respect to all the variables included in the analysis.     

The Benefit Function Approach to Modeling Price-Dependent Demand Systems: An Application of Duality Theory

In this article, we advocate more extensive use of the benefit function in specifying price-dependent or inverse demand models. We demonstrate how duality theory may be used to establish the interrelationships between the Marshallian (or Hicksian) inverse demands and Luenberger's adjusted price functions, allowing estimable inverse demands to be derived directly from a benefit function. We estimate two systems of inverse demands for Japanese quarterly fish consumption. Results indicate that the procedures and methods employed here appear promising, and may prove beneficial for quantity and welfare analysis when modeling systems of inverse demand functions.     

Using Consumption and Asset Return Data to Estimate Farmers' Time Preferences and Risk Attitudes

The generalized expected utility model is fitted to U.S. farm data to estimate farm operator's time preferences and risk attitudes. The estimated farmer's utility parameters are quite 'reasonable' and exhibit high accuracy. The forward-looking expected utility model is soundly rejected in favor of the generalized expected utility paradigm. Importantly, the generalized expected utility model is also found to fit the data better than the myopic model typically used to study agricultural production under risk. Finally, U.S. farmers' relative aversion to risk appears to have diminished significantly over time.     

风景区委托——代理管理模型探讨

针对城市园林管理问题，建立量化的游人消费价值模型和效用函数，运用博弈论分析了城市园林管理模型的纳什均衡。在借鉴信息经济学理论的基础上，提出了景区管理的委托——代理管理模型，提出了加强景区管理的具体措施。     

Risk Management for Grain Processors and “Copulas”

The importance of calibrating hedging strategies for processors has escalated primarily due to the sharply increased volatility of futures, product, and by‐product prices. The purpose of this paper is to analyze price risk‐management strategies for wheat flour milling using copula distributions. While the application is for flour milling, it has similarities with other processing industries which confront one or more ingredients, one or more outputs, and futures for one of the commodities and/or products. The paper develops utility maximizing models encompassing expected return and risk. Alternative scenarios are evaluated. First, the models were used to derive optimal hedge ratios, as well as various measures of risk and return under alternative scenarios, and hedge durations. The results indicated hedge ratios are typically less than 1. The hedge ratios for the Mean‐value‐at‐risk (M‐VaR)‐Copula model increased with greater durations. Second, the VaR for the M‐VaR‐Copula was in most cases less than the noncopula specifications. Thus, noncopula models may over state risk as represented by VaR.     

Impacts of risk aversion on whole-farm management in Syria

This article reports on a study of the impact of risk on farm management practices in northern Syria, focusing particularly on how these are affected by risk aversion and farm size. The study is based on production data from an eight-year field trial and on prices from market surveys. A large linear programming model is built, representing the eight years as observations from a discrete probability distribution. Risk aversion is modelled by inclusion of a utility function with constant relative risk aversion, represented using the DEMP/UEP approach.     

Pricing Organic Nitrogen Under The Weak Disposability Assumption: An Application to the French Pig Sector

The nonparametric approach Data Envelopment Analysis is used in order to measure individual technical inefficiency. Different models are evaluated using a 1991 FADN data set of French pig farms. Organic nitrogen is considered as a byproduct of animal breeding. Used as plant nutrient, organic manure becomes an input in crop production which is pollutant when excessive amounts enter surface and groundwater. In the latter case, the usual hypothesis of strong disposability of organic nitrogen is refuted because the elimination of pollution is costly. In this paper, we introduce a hypothesis of weak disposability of organic nitrogen and compare the technical efficiency measures obtained with and without this assumption. Then, using the duality between the restricted cost function and the input-output distance function and following Färe and Primont (1995), we derive a shadow price of organic nitrogen which can be compared to the unit cost of different existing manure treatments.     

THE USE OF A DECISION MAKER'S UTILITY FUNCTION IN A LINEAR PROGRAMMING ANALYSIS OF AGRICULTURAL POLICY*

A decision theoretic approach to agricultural policy decision making is examined to discover whether a utility function of an Australian Wool Corporation decision maker can be established and, if so, whether this can be used to improve the policy analysing performance of an agricultural sector linear programming model. After discussing the theoretical requirements of the utility function elicitation and the elicitation procedures, the characteristics of the resulting functions are examined. A means for its inclusion in a linear programming framework is described and some analysis of policy is carried out. The general conclusions are that the relevance of the agricultural sector analysis is enhanced by the use of such a utility function.     

THE OUTPUT RESPONSE OF THE RISK AVERSE FIRM: SOME COMPARATIVE STATICS FOR AGRICULTURAL POLICY

The policy conclusions which stem from the deterministic theory of the competitive firm are well known and unambiguous. However, once product price is regarded as stochastic, there exist several theories upon which to base an analysis of the impact of agricultural policy on the output response of the firm. The paper considers four models from the safety-first and expected utility frameworks. These models produce a diverse set of comparative statics results which in many instances conflict with those of the deterministic model. Hence, the paper concludes that it is important in agricultural policy analysis that greater consideration by given to the links between risk aversion, policy-induced uncertainty and output response than is conventionally the case.     

Principles of stochastic dynamic optimization in resource management: the continuous-time case

A wide range of problems in economics, agriculture, and natural resource management have been analyzed using continuous-time optimal control models, where the state variables change over time in a stochastic manner. Using a firm-level investment model and a model of environmental degradation, this paper provides a concise introduction to continuous-time stochastic control techniques. The process used to derive the differential of a stochastic process is stressed and, in turn, is used to explain Ito's lemma, Bellman's equation, the Hamilton-Jacobi equation, the maximum principle, and the expected dynamics of choice variables. A basic extension of the dynamic duality literature is also provided, where the Hamilton-Jacobi equation is used to derive a stochastic and dynamic analogue of Hotelling's lemma.     

Multi‐Criteria Analysis of Input Use in Agriculture

In this paper we present a methodology for the analysis of input use in the agricultural sector. The novelty of the theoretical model described here is that it has been developed considering a multi‐criteria environment. Thus, the optimal input use condition is determined by evaluating “multi‐attribute utility” and “multi‐attribute marginal utility”. We show how the approach adopted in this paper is a generalisation of the single‐attribute expected utility theory. The theoretical model developed is thereafter implemented in an empirical application that studies water for irrigation use as a particular case. The results show how multi‐attribute utility functions elicited for a sample of 52 irrigators explain differences in irrigation water use in relatively homogeneous agricultural systems, albeit exhibiting dissimilar partial utility functions for water use. We conclude that these differences come from the dissimilar weights that farmers attach to each attribute in the aggregate utility function.     

The Use of Conditional Cost Functions to Generate Estimable Mixed Demand Systems

Mixed demand systems have been virtually ignored in empirical work solely because derivation of these systems requires closed forms for both direct and indirect utility functions. This article proposes the alternative of using a conditional cost function to generate empirical mixed demand models. This approach allows the estimation of mixed demand systems, which are explicit in an unobservable variable (utility), but may lack a closed form representation in terms of observable variables such as prices, quantities and expenditure. Results indicate that this approach is operationally feasible, which opens up a wider range of mixed demand specifications in static analyses.     

Choice of utility function form: its effect on classification of risk preferences and the prediction of farmer decisions

In applications of expected utility analysis, researchers are confronted with a choice among several utility functional forms. Subjective utility values and probability distributions for price and yield were elicited from Sri Lankan producers of minor export crops. Exponential quadratic and cubic utility functions were estimated. The choice of functional form was found to affect both the classification of risk attitudes and the prediction of harvesting strategy. The exponential function was the best predictor of harvesting strategy because it was the best predictor of mature harvesting. All three functions were equally poor predictors of premature harvesting.     

基于序期望效用的洪水保险需求研究

在序期望效用决策框架下对洪水保险的投保行为进行建模,通过假设洪水保险的投保人的风险偏好是一阶风险厌恶的,得出和期望效用决策理论下不一致的结果,分析了序期望效用下的免赔额数学模型的经济学意义,并得出结论：免赔额的设置与保费附加费系数的高低将对洪水保险的有效需求造成影响。     

Effect of yield and price risk on conversion from conventional to organic farming*

Although the benefits of organic farming are already well known, the conversion to organic farming does not proceed as the Dutch government expected. In order to investigate the conversion decisions of Dutch arable farms, a discrete stochastic dynamic utility‐efficient programming (DUEP) model is developed with special attention for yield and price risk of conventional, conversion and organic crops. The model maximizes the expected utility of the farmer depending on the farmer’s risk attitude. The DUEP model is an extension of a dynamic linear programming model that maximized the labour income of conversion from conventional to organic farming over a 10 year planning horizon. The DUEP model was used to model a typical farm for the central clay region in the Netherlands. The results show that for a risk‐neutral farmer it is optimal to convert to organic farming. However, for a more risk‐averse farmer it is only optimal to fully convert if policy incentives are applied such as taxes on pesticides or subsidies on conversion, or if the market for the organic products becomes more stable.     

How do planners manage risk in alternative land development models? An institutional analysis of land development in the Netherlands

While risk is a key concern in property development, it tends to be discussed by planners only relative to the effects of regulatory planning on private sector risk. Yet planning encompasses a broad range of activities that go beyond its function of regulating private sector development. Despite active approaches to land development being commonly used across different planning contexts, frameworks for analysing public sector strategies to address risk are rarely discussed. We attempt to redress this deficit by investigating the actions of public sector development actors with regard to risk across three different land development models: public land development, land development by public-private partnership, and land readjustment. Using recent Dutch experience, we conduct an institutional analysis of each land development model in order to highlight the effects of alternative governance structures on risk as a particular transaction attribute, from the perspective of public sector planning. Our findings indicate the importance of highlighting the role of public risk in alternative models of land development where there may be a tendency to adopt institutional arrangements without due regard to this, and point to possible future applications of institutional analysis at the particular, rather than the general, level.