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Registros recuperados: 38
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A BAYESIAN ALTERNATIVE TO GENERALIZED CROSS ENTROPY SOLUTIONS FOR UNDERDETERMINED ECONOMETRIC MODELS AgEcon
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.
Tipo: Working or Discussion Paper 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
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Adaptive Experimental Design Using the Propensity Score AgEcon
Hahn, Jinyong; Hirano, Keisuke; Karlan, Dean S..
Many social experiments are run in multiple waves, or are replications of earlier social experiments. In principle, the sampling design can be modified in later stages or replications to allow for more efficient estimation of causal effects. We consider the design of a two-stage experiment for estimating an average treatment effect, when covariate information is available for experimental subjects. We use data from the first stage to choose a conditional treatment assignment rule for units in the second stage of the experiment. This amounts to choosing the propensity score, the conditional probability of treatment given covariates. We propose to select the propensity score to minimize the asymptotic variance bound for estimating the average treatment...
Tipo: Working or Discussion Paper Palavras-chave: Experimental design; Propensity score; Efficiency bound; Research Methods/ Statistical Methods; C1; C14; C9; C93; C13.
Ano: 2009 URL: http://purl.umn.edu/47107
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Agricultural Technology Adoption and Rural Poverty: Application of an Endogenous Switching Regression for Selected East African Countries AgEcon
Asfaw, Solomon; Shiferaw, Bekele A..
Achieving agricultural growth and development and thereby improving rural household welfare will require increased efforts to provide yield enhancing and natural resources conserving technologies. Agricultural research and technological improvements are therefore crucial to increase agricultural productivity and thereby reduce poverty. However evaluation of the impact of these technologies on rural household welfare have been very limited by lack of appropriate methods and most of previous research has therefore failed to move beyond estimating economic surplus and return to research investment. This paper evaluates the potential impact of adoption of modern agricultural technologies on rural household welfare measured by crop income and consumption...
Tipo: Conference Paper or Presentation Palavras-chave: Rural household welfare; Technology adoption; Propensity score matching; Endogenous switching; Ethiopia; Tanzania; Food Security and Poverty; Research and Development/Tech Change/Emerging Technologies; C13; C15; O32; O38.
Ano: 2010 URL: http://purl.umn.edu/97049
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An Information-Theoretic Approach to Modeling Binary Choices: Estimating Willingness to Pay for Recreation Site Attributes AgEcon
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
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At Home and Abroad: An Empirical Analysis of Innovation and Diffusion in Energy-Efficient Technologies AgEcon
Verdolini, Elena; Galeotti, Marzio.
This paper contributes to the induced innovation literature by extending the analysis of supply and demand determinants of innovation in energy-efficient technologies to account for international knowledge flows and spillovers. In the first part of the paper we select a sample of 38 innovating countries and we study how knowledge related to energy-efficient technologies flows across geographical and technological space. We demonstrate that higher geographical and technological distances are associated with a lower probability of knowledge flow. In the second part of the paper, we use our previous estimates to construct stocks of internal and external knowledge for a panel of 17 countries and present an econometric analysis of the supply and demand...
Tipo: Working or Discussion Paper Palavras-chave: Innovation; Technology Diffusion; Knowledge Spillovers; Energy-Efficient Technologies; Resource /Energy Economics and Policy; O33; Q55; C13.
Ano: 2009 URL: http://purl.umn.edu/56216
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BANDWIDTH SELECTION FOR SPATIAL HAC AND OTHER ROBUST COVARIANCE ESTIMATORS AgEcon
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...
Tipo: Working or Discussion Paper 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
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BANDWIDTH SELECTION FOR SPATIAL HAC AND OTHER ROBUST COVARIANCE ESTIMATORS AgEcon
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...
Tipo: Working or Discussion Paper Palavras-chave: Spatial HAC; Semivariogram; Bandwidth; Hedonic model; Research Methods/ Statistical Methods; C13; C31; R21.
Ano: 2008 URL: http://purl.umn.edu/45964
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Determinants of Rural-Urban Migration in Konkan Region of Maharashtra AgEcon
Thorat, V.A.; Dhekale, J.S.; Patil, H.K.; Tilekar, S.N..
The study has identified the factors responsible for rural-urban migration based on 120 sample respondents each of migrants and non-migrants spread over two districts, viz. Ratnagiri and Sindhudurg of Konkan region of Maharashtra by employing the logit model. The study has highlighted the importance of rural development programs like MGNREGA that are being implemented by the government with a view to provide employment and income to the rural population in the country. It has also shown that for both migrant and non-migrant households,, agriculture was the major source of income, and their consumption expenditure was more than the production expenditure. It has also been observed that migration has a positive impact on income, expenditure and net savings...
Tipo: Article Palavras-chave: Migration; Logit; Variable inflation factor; Odds ratio; Agricultural and Food Policy; J11; J61; C13; R23.
Ano: 2011 URL: http://purl.umn.edu/119399
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Determining the change in welfare estimates from introducing measurement error in non-linear choice models AgEcon
Gibson, Fiona L.; Burton, Michael P..
Observed and unobserved characteristics of an individual are often used by researchers to explain choices over the provision of environmental goods. One means for identifying what is typically an unobserved characteristic, such as an attitude, is through some data reduction technique, such as factor analysis. However, the resultant variable represents the true attitude with measurement error, and hence, when included into a non-linear choice model, introduces bias in the model. There are well established methods to overcome this issue, which are seldom implemented. In an application to preferences over two water source alternatives for Perth in Western Australia, we use structural equation modeling within a discrete choice model to determine whether...
Tipo: Working or Discussion Paper Palavras-chave: Contingent valuation; Attitudes; Structural equation modeling; Recycled water; Environmental Economics and Policy; Research Methods/ Statistical Methods; Q51; Q53; C13.
Ano: 2011 URL: http://purl.umn.edu/103428
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Economic techniques to estimate the demand for sustainable products: a case study for fair trade and organic coffee in the United Kingdom AgEcon
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
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Empirical evidence on the role of non linear wholesale pricing and vertical restraints on cost pass-through AgEcon
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
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Estimating a Demand System with Seasonally Differenced Data AgEcon
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
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ESTIMATING COKE AND PEPSI'S PRICE ADVERTISING STRATEGIES AgEcon
Golan, Amos; Karp, Larry S.; Perloff, Jeffrey M..
AgEcon Search copy replaced with 1999 version 02/02/06.
Tipo: Working or Discussion Paper Palavras-chave: Strategies; Noncooperative games; Oligopoly; Generalized maximum entropy; Beverages; Marketing; C13; C35; C72; L13; L66.
Ano: 1997 URL: http://purl.umn.edu/25057
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Estimating State-Contingent Production Functions AgEcon
Rasmussen, Svend; Karantininis, Kostas.
The paper reviews the empirical problem of estimating state-contingent production functions. The major problem is that states of nature may not be registered and/or that the number of observation per state is low. Monte Carlo simulation is used to generate an artificial, uncertain production environment based on Cobb Douglas production functions with state-contingent parameters. The parameters are subsequently estimated based on different sizes of samples using Generalized Least Squares and Generalized Maximum Entropy and the results are compared. It is concluded that Maximum Entropy may be useful, but that further analysis is needed to evaluate the efficiency of this estimation method compared to traditional methods.
Tipo: Conference Paper or Presentation Palavras-chave: Maximum entropy; State-contingent; Uncertainty; Production; Monte Carlo simulation; Production Economics; C13; C15; D80.
Ano: 2005 URL: http://purl.umn.edu/24529
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Estimation and Inference for Threshold Effects in Panel Data Stochastic Frontier Models AgEcon
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...
Tipo: Conference Paper or Presentation 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
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Estimation of Actual and potential adoption rates and determinants of a new technology not universally known in the population: The case of NERICA rice varieties in Guinea AgEcon
Diagne, Aliou; Sogbossi, Marie-Josee; Simtowe, Franklin; Diawara, Sekou; Diallo, Abdoulaye Sadio; Barry, Alpha Bacar.
The NERICA (New Rice for Africa) rice varieties, developed by the Africa Rice Center during the 1990s, are providing hopes for raising the productivity of upland rice farmers in Africa because of their reported high yield potential and adaptability to the African conditions. The varieties are new and not widely disseminated in farming communities and there is lot of interest in the donor community in knowing their potential for widespread adoption across sub-Saharan Africa (SSA). However, when a technology is new and the target population is not universally exposed it, the observed sample adoption rate and classical models of adoption widely used in adoption studies does not inform reliably on its potential adoption and constraint to it in the full...
Tipo: Conference Paper or Presentation Palavras-chave: NERICA varieties; Technology Diffusion and adoption; Average Treatment Effect; Guinea; International Development; Research Methods/ Statistical Methods; C13; O33; Q12; Q16.
Ano: 2009 URL: http://purl.umn.edu/51644
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Estimation of Agricultural Total Factor Productivity in China: A Panel Cointegration Approach AgEcon
Wang, Jintian; Gao, Feng; Wang, Xuezhen.
Using a panel cointegration approach to estimate the agricultural total factor productivity in China
Tipo: Conference Paper or Presentation Palavras-chave: Total Factor Productivity; Panel Unit Root; Panel Cointegration; DOLS; FMOLS; Productivity Analysis; C13; C23; Q00.
Ano: 2009 URL: http://purl.umn.edu/50927
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FARM HOUSEHOLD EFFICIENCY IN MOZAMBIQUE AgEcon
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...
Tipo: Conference Paper or Presentation Palavras-chave: Stochastic frontier analysis; Farm production efficiency; Productivity Analysis; C12; C13.
Ano: 2009 URL: http://purl.umn.edu/51438
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From small farming to rural, non-agricultural work in Romania: an evaluation on 3 measures of the rural development programme AgEcon
Ghib, Marie-Luce; Berriet-Solliec, Marielle.
Romanian rural areas contain the highest level of agricultural workers in the European Union, resulting in the challenge of stimulating non-agricultural employment. This paper uses the methodology of policy evaluation to analyse the influence of 3 measures the CAP. From an objectives tree to reveal the objectives of the programme to statistical analysis and field surveys, we analysed the pertinence, the coherence and the first results of those schemes. It was found that the targeted population was under estimated for one of the semi-subsistence schemes. Choosing activities (tourism and enterprise) which are open to all rural society leads to enhanced competition between beneficiaries. Due to the global context of economic crisis, co-financing can be met...
Tipo: Conference Paper or Presentation Palavras-chave: Rural policies; Policy evaluation; Small farms; Romania; Community/Rural/Urban Development; R58; O21; H72; C13.
Ano: 2010 URL: http://purl.umn.edu/94915
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How Much Can We Learn About Producers' Utility Functions from Their Production Data? AgEcon
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
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