SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Brown, Zachary S.; Bellemare, Marc F..

We develop a method to structurally estimate principal-agent models by ordinary least squares (OLS). We set up a general principal-agent model which explicitly incorporates the wealth levels of each party and the opportunity cost to the agent of entering the contract. This yields an optimal contract that is linearized by way of an Nth order Taylor approximation. This in turn imposes N(3N-1)/2 restrictions on the parameters and yields an empirical test of the canonical principal-agent model. In the application, we consider the case where N = 2 and apply our method to a sample of land tenancy contracts in rural Madagascar. Empirical tests lead to consistent failure to reject the hypotheses derived from our structural model, which lends support to our...

REGULATING IRRIGATION VIA BLOCK-RATE PRICING: AN ECONOMETRIC ANALYSIS

Palavras-chave: Principal-Agent Models; Contract Theory; Structural Estimations; Risk and Uncertainty; C12; C13; D86; O12; Q12.

Ano: 2009

URL: http://purl.umn.edu/49368

Bar-Shira, Ziv; Finkelshtain, Israel; Simhon, Avi.

In this paper, we adapt Burtless and Hausman's (1978) methodology in order to estimate farmer's demand for irrigation water under increasing block-rate tariffs and empirically assess its effect on aggregate demand and inter-farm allocation efficiency. This methodology overcomes the technical challenges raised by increasing block rate pricing and accounts for both observed and unobserved technological heterogeneity among farmers. Employing a micro panel data documenting irrigation levels and prices in 185 Israeli agricultural communities in the period 1992-1997 we estimate water demand elasticity at -0.3 in the short run (the effect of a price change on demand within a year of implementation) and -0.46 in the long run. We also find that, in...

Valoracion del agua de riego por el metodo de precios quasi-hedonicos: aplicacion al Guadalquivir

Palavras-chave: Block-Rate Pricing; Irrigation; C13; Q15; Q28; Resource /Energy Economics and Policy.

Ano: 2005

URL: http://purl.umn.edu/14982

Berbel, Julio; Mesa, Pascual.

La estimación del valor del agua puede hacerse mediante diferentes métodos, de los cuales este trabajo propone el método de precios "quasi-hedónicos". El agua se considera en este trabajo como una variable externa que impacta en el precio diferencial de la tierra, y cuyo valor estimamos para la Cuenca del Guadalquivir. Los resultados nos muestran un valor capital del agua en el rango 2,8 €/m3 a 4,2 €/m3 con un valor más frecuente de 3,46 €/m3, que según el tipo de capitalización empleado nos daría un valor medio de renta del agua entre 0,14 €/m3 (para r=4%) a 0,35 €/m3 (para r=10%). ABSTRACT The valuation of natural resources is a tool used for improving allocation and management of water resources. This research proposes a quasi-hedonic approach as a...

Tipo: Journal Article

Palavras-chave: Irrigated agriculture; Hedonic price; Environmental valuation; Water value; Agricultura de riego; Precios hedónicos; Valoracion ambiental; Valor del agua; Resource /Energy Economics and Policy; Q25; C13.

Ano: 2007

URL: http://purl.umn.edu/7059

FARM HOUSEHOLD EFFICIENCY IN MOZAMBIQUE

Uaiene, Rafael N.; Arndt, Channing.

This article provides estimates of farm household efficiency and its determinants among smallholder farmers in Mozambique. A translog stochastic frontier production function and a first difference model incorporating a model of farm household inefficiency effects are applied to test the existence of agricultural farm household inefficiencies and their determinants in Mozambique. The null hypothesis of equal farm household efficiency among households was rejected. Variation in farm household efficiency indicates that access to agricultural technology is a severe constraint for most farm households. Factors such as access to advisory services, access to rural credit, membership to an agricultural association, use of improved agricultural technology...

Joint Estimation of Risk Preferences and Technology: Flexible Utility of Futility?

Palavras-chave: Stochastic frontier analysis; Farm production efficiency; Productivity Analysis; C12; C13.

Ano: 2009

URL: http://purl.umn.edu/51438

Lence, Sergio H..

The present study sets up a thought experiment calibrated to represent risks of a high-risk production activity (farming), and investigating whether the structure of risk aversion (i.e., the changes in absolute or relative risk aversion associated with changes in wealth) can be estimated with reasonable precision. Findings strongly suggest that typical production data are unlikely to allow identification of the structure of risk aversion. A flexible utility parameterization is found to worsen technology parameter estimates. Findings also indicate that even under a restricted utility specification, the quality of utility parameters estimated from small samples is very poor.

An Information-Theoretic Approach to Modeling Binary Choices: Estimating Willingness to Pay for Recreation Site Attributes

Palavras-chave: Expected utility; Risk preferences; Production analysis; Risk attitudes.; Risk and Uncertainty; C13; D24; D81; Q12..

Ano: 2007

URL: http://purl.umn.edu/9980

Henry-Osorio, Miguel; Mittelhammer, Ronald C..

Information-Theoretic Econometrics

Tipo: Presentation

Palavras-chave: Minimum power divergence; Cressie-Read statistics; Contingent valuation; Empirical likelihood; Discrete choice; Binary response models; Environmental Economics and Policy; Research Methods/ Statistical Methods; C13; C14; C25; Q51.

Ano: 2012

URL: http://purl.umn.edu/123432

The determinants of bilateral World Trade Organization disputes in the agro-food sector

Goetz, Christian; Heckelei, Thomas.

This paper analyses relevant determinants for the probability to initiate a dispute on policy measures under the World Trade Organization (WTO) dispute settlement system. The empirical analysis focuses on agro-food-related disputes to provide sector-specific information on the driving factors in dispute settlement, and complements and extends previous studies by incorporating new potential determinants. The focus is shifted to bilaterally dependent characteristics to take care of trade related and power-based relationships between Members. Contrary to recent analyses of overall trade disputes, the results show that some determinants such as export value and monetary means are not statistically significant. However, the import dependency from the defendant...

BANDWIDTH SELECTION FOR SPATIAL HAC AND OTHER ROBUST COVARIANCE ESTIMATORS

Palavras-chave: WTO dispute; Agro-food sector; Binary choice model; International Relations/Trade; C12; C13; F13.

Ano: 2009

URL: http://purl.umn.edu/49461

Lambert, Dayton M.; Florax, Raymond J.G.M.; Cho, Seong-Hoon.

This research note documents estimation procedures and results for an empirical investigation of the performance of the recently developed spatial, heteroskedasticity and autocorrelation consistent (HAC) covariance estimator calibrated with different kernel bandwidths. The empirical example is concerned with a hedonic price model for residential property values. The first bandwidth approach varies an a priori determined plug-in bandwidth criterion. The second method is a data driven cross-validation approach to determine the optimal neighborhood. The third approach uses a robust semivariogram to determine the range over which residuals are spatially correlated. Inference becomes more conservative as the plug-in bandwidth is increased. The data-driven...

Poverty Comparisons with Endogenous Absolute Poverty Lines

Palavras-chave: Spatial HAC; Semivariogram; Bandwidth; Hedonic model; Community/Rural/Urban Development; Demand and Price Analysis; Land Economics/Use; Research Methods/ Statistical Methods; C13; C31; R21.

Ano: 2008

URL: http://purl.umn.edu/44258

Simler, Kenneth R.; Arndt, Channing.

The objective of measuring poverty is usually to make comparisons over time or between two or more groups. Comm on statistical inference methods are used to determine whether an apparent difference in measured poverty is statistically significant. Studies of relative poverty have long recognized that when the poverty line is calculated from sample survey data, both the variance of the poverty line and the variance of the welfare metric contribute to the variance of the poverty estimate. In contrast, studies using absolute poverty lines have ignored the poverty line variance, even when the poverty lines are estimated from sample survey data. Including the poverty line variance could either reduce or increase the precision of poverty estimates, depending on...

BANDWIDTH SELECTION FOR SPATIAL HAC AND OTHER ROBUST COVARIANCE ESTIMATORS

Palavras-chave: Poverty measurement; Bootstrap; Mozambique; Food Security and Poverty; I32; C13; 012.

Ano: 2006

URL: http://purl.umn.edu/25775

Lambert, Dayton M.; Florax, Raymond J.G.M.; Cho, Seong-Hoon.

Economic techniques to estimate the demand for sustainable products: a case study for fair trade and organic coffee in the United Kingdom

Palavras-chave: Spatial HAC; Semivariogram; Bandwidth; Hedonic model; Research Methods/ Statistical Methods; C13; C31; R21.

Ano: 2008

URL: http://purl.umn.edu/45964

Galarraga, Ibon; Markandya, Anil.

The hedonic approach is used in this paper to estimate how much is paid for the fair trade/organic characteristic of the coffee in the British market. This information is later combined with the Quantity Based Demand System (QBDS) model -developed by the authors- and the Almost Ideal Demand System (AIDS) (Deaton and Muellbauer, 1980) to completely determine the demand function for different coffees. The QBDS model is easier to handle and less data demanding than the AIDS model in this study. Resumen El presente artículo se basa en la utilización del método hedónico para la estimación de la cantidad que se paga por la característica de "Orgánico/Comercio Justo" del café en el mercado británico. La información obtenida se combina después con el modelo...

Tipo: Journal Article

Palavras-chave: Demand systems; Hedonic method; Coffee demand; Labelling; C13; C21; D12.

Ano: 2004

URL: http://purl.umn.edu/28732

The Effect of Climate Change, CO2 Fertilization, and Crop Production Technology on Crop Yields and Its Economic Implications on Market Outcomes and Welfare Distribution

Attavanich, Witsanu; McCarl, Bruce A..

Many studies have done econometric estimates of how climate alters crop yields and or land rents in an effort to gain information on potential effects of climate change. However, an important related factor, the atmospheric carbon dioxide (CO2) concentration, and in fact a driver of climate change is ignored. This means the prior econometric estimates are biased as they infer what will happen under climate change from observations in the recent past, but without consideration of CO2 effects. Furthermore although CO2 has been varying, it has proceeded at a very linear pace and cannot be disentangled from technological progress using historical crop yield data. This paper is designed to overcome this issue and estimate the consequences that CO2 has and...

Estimation and Inference for Threshold Effects in Panel Data Stochastic Frontier Models

Palavras-chave: Carbon Dioxide Fertilization; Crop Yield; Yield Variability; Climate Change; Crop Production Technology; Welfare Distribution; Market Outcomes; Stochastic Production Function; The Agricultural Sector Model; Feasible Generalized Least Squares; Crop Production/Industries; Land Economics/Use; Production Economics; Research and Development/Tech Change/Emerging Technologies; C61; C13; Q16; Q54; D69; D24.

Ano: 2011

URL: http://purl.umn.edu/103324

Yelou, Clement; Larue, Bruno; Tran, Kien C..

One of the most enduring problems in cross-section or panel data models is heterogeneity among individual observations. Different approaches have been proposed to deal with this issue, but threshold regression models offer intuitively appealing econometric methods to account for heterogeneity. We propose three different estimators that can accommodate multiple thresholds. The first two, allowing respectively for fixed and random effects, assume that the firms specific inefficiency scores are time-invariant while the third one allows for time-varying inefficiency scores. We rely on a likelihood ratio test with m − 1 regimes under the null against m regimes. Testing for threshold effects is problematic because of the presence of a nuisance parameter which...

Estimating a Demand System with Seasonally Differenced Data

Palavras-chave: Stochastic frontier models; Threshold regression; Technical efficiency; Bootstrap; Dairy production; C12; C13; C23; C52; Research Methods/ Statistical Methods.

Ano: 2007

URL: http://purl.umn.edu/9769

Harri, Ardian; Brorsen, B. Wade; Muhammad, Andrew; Anderson, John D..

Several recent papers have used annual changes and monthly data to estimate demand systems. Such use of overlapping data introduces a moving average error term. This paper shows how to obtain consistent and asymptotically efficient estimates of a demand system using seasonally differenced data. Monte Carlo simulations and an empirical application to the estimation of the U.S. meat demand are used to compare the proposed estimator with alternative estimators. Once the correct estimator is used, there is no advantage to using overlapping data in estimating a demand system.

Tipo: Journal Article

Palavras-chave: Autocorrelation; Demand system; Monte Carlo; Overlapping data; Seasonal differences; Agribusiness; Demand and Price Analysis; Financial Economics; Research Methods/ Statistical Methods; C13; Q11; Q13.

Ano: 2010

URL: http://purl.umn.edu/90679

Empirical evidence on the role of non linear wholesale pricing and vertical restraints on cost pass-through

Bonnet, Céline; Dubois, Pierre; Villas-Boas, Sofia Berto.

How a cost shock is passed through into final consumer prices may relate to nominal price stickiness and rigidities, the existence of non adjustable cost components, strategic mark-up adjustments, or other contract terms along the supply distribution chain. This paper presents a simple framework to assess the potential role of non linear pricing contracts and vertical restraints such as resale price maintenance or wholesale price discrimination in the supply chain in explaining the degree of pass-through from upstream cost shocks in the ground coffee category to downstream retail prices. We do so in the German coffee market where both upstream and downstream firms make pricing decisions allowing for non linear pricing and vertical restraints. Using...

Tipo: Working Paper

Palavras-chave: Non Linear Pricing; Multiple Manufacturers and Retailers; Ground Coffee; Pass-Through; Resale Price Maintenance; Wholesale Price Discrimination; Consumer/Household Economics; C13; L13; L41.

Ano: 2009

URL: http://purl.umn.edu/120534

To Target or Not to Target? The cost efficiency of indicator-based targeting

Houssou, Nazaire; Zeller, Manfred.

This paper assesses the cost efficiency of indicator-based targeting. Using household survey data from Malawi, we examine whether an indicator-based targeting of the poor is more target- and cost-efficient than the currently used mechanisms for targeting agricultural subsidy programs in the country. There is compelling evidence in favor of targeting Malawi’s poor based on the newly developed system. An indicator-based targeting system appears to be more target- and cost-efficient than the 2000/01 Starter Pack and the 2006/07 Agricultural Input Subsidy Program (AISP). While the Starter Pack and the AISP transferred about 50% of total transfer, under an indicator-based system, about 73% of transfers are delivered to the poor. Likewise, under an...

A BAYESIAN ALTERNATIVE TO GENERALIZED CROSS ENTROPY SOLUTIONS FOR UNDERDETERMINED ECONOMETRIC MODELS

Palavras-chave: Malawi; Poverty targeting; Validation tests; Cost efficiency; Development policy; Agricultural and Food Policy; Community/Rural/Urban Development; Food Security and Poverty; Political Economy; Research Methods/ Statistical Methods; C01; C13; I32.

Ano: 2010

URL: http://purl.umn.edu/61007

Heckelei, Thomas; Mittelhammer, Ronald C.; Jansson, Torbjorn.

This paper presents a Bayesian alternative to Generalized Maximum Entropy (GME) and Generalized Cross Entropy (GCE) methods for deriving solutions to econometric models represented by underdetermined systems of equations. For certain types of econometric model specifications, the Bayesian approach provides fully equivalent results to GME-GCE techniques. However, in its general form, the proposed Bayesian methodology allows a more direct and straightforwardly interpretable formulation of available prior information and can reduce significantly the computational effort involved in finding solutions. The technique can be adapted to provide solutions in situations characterized by either informative or uninformative prior information.

Meta-Regression Estimates for CGE Models: A Case Study for Input Substitution Elasticities in Production Agriculture

Palavras-chave: Underdetermined Equation Systems; Maximum Entropy; Bayesian Priors; Structural Estimation; Calibration; Research Methods/ Statistical Methods; C11; C13; C51.

Ano: 2008

URL: http://purl.umn.edu/56973

Boys, Kathryn A.; Florax, Raymond J.G.M..

The selection of appropriate parameters for computable general equilibrium (CGE) models critically affects the results of applied economic modeling exercises. Valid and reliable parameter selection models are needed, and typically comprise direct estimation, expert opinion, or copycatting of results from seminal studies. The purpose of this study is to use meta-analysis to summarize and more accurately estimate elasticities of input substitution, specifically between labor and other inputs in agricultural production. We construct a comprehensive database of elasticity estimates through an extensive literature review, and perform a meta-regression analysis to identify structural sources of variation in elasticity estimates sampled from primary studies. The...

How Much Can We Learn About Producers' Utility Functions from Their Production Data?

Palavras-chave: Meta-analysis; Cross-price elasticity; Input substitu¬tion; Agricultural production; CGE parameters; Demand and Price Analysis; C13; C68; Q13.

Ano: 2007

URL: http://purl.umn.edu/9683

Operational Models for Improving the Targeting Efficiency of Agricultural and Development Policies: A systematic comparison of different estimation methods using out-of-sample tests

Lence, Sergio H..

A thought experiment is designed to investigate whether the structure of risk aversion (i.e., the changes in absolute or relative risk aversion associated with changes in wealth) can be estimated with reasonable precision from agricultural production data. Findings strongly suggest that typical production data are unlikely to allow identification of the structure of risk aversion. A flexible utility parameterization is found to slightly worsen technology parameter estimates. Results also indicate that even under a restricted utility specification, utility parameter estimates are biased. Further, their quality is much worse when shocks are not large or samples are small.

Tipo: Presentation

Palavras-chave: Expected utility; Risk preferences; Production analysis; Risk attitudes; Production Economics; Risk and Uncertainty; C13; D24; D81; Q12.

Ano: 2008

URL: http://purl.umn.edu/119534

Houssou, Nazaire; Zeller, Manfred.

Accurate targeting is key for the success of any development policy. While a number of factors might explain low targeting efficiency such as governance failure, political interference or lack of political will, this paper focuses on improving indicator-based models that identify poor households and smallholder farmers more accurately. Using stepwise regressions along with out-of-sample validation tests and receiver operating characteristic curves, this paper develops proxy means tests models for rural and urban Malawi. The models developed have proved their validity in an independent sample and therefore, can be used to target a wide range of development policies to the poor. This makes the models a potentially interesting policy tool for the country.