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Registros recuperados: 29
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Measuring the Determinants of School Completion in Pakistan: Analysis of Censoring and Selection Bias AgEcon
Holmes, Jessica.
This paper explores the demand for child schooling in Pakistan, using the Pakistan Integrated Household Survey (1991). There have been few such studies for Pakistan, a country with relatively low enrollment rates and education levels, high illiteracy, and large disparity between male and female education. Additionally, this study focuses on two potential sources of bias in the estimation of the demand for schooling. First, studies which do not distinguish between currently enrolled children and those who have completed their schooling subject their estimates to a form of censoring bias. Second, studies which exclude children who have left the household from their samples may introduce sample selection bias if the decisions to leave home and to attend...
Tipo: Working or Discussion Paper Palavras-chave: Labor and Human Capital; I2; C24.
Ano: 1999 URL: http://purl.umn.edu/28530
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Spanish Demand for Food Away From Home: A Panel Data Approach AgEcon
Angulo, Ana Maria; Gil, Jose Maria; Mur, Jesus.
In this paper, the Spanish demand for food away from home is analysed. A panel data set is built and appropriate techniques for estimating limited dependent variable models have been applied. Results indicate that where there are zero expenditures, these are largely due to infrequency of purchase rather than to abstention or to economic reasons. Furthermore, important differences appear among households. On the one hand, those households whose head is a highly-educated person, male, young and living on a salary in a large town are more likely to purchase food away from home. On the other hand, increases in income only provokes more than proportional increases in expenditure for those households headed by an unschooled person, a female or a person older...
Tipo: Conference Paper or Presentation Palavras-chave: Demand for food away from home; Household production theory; Panel data.; Consumer/Household Economics; C23; C24; D12.
Ano: 2002 URL: http://purl.umn.edu/24977
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The Role of On-Site Time in Recreational Demand for Wilderness AgEcon
Acharya, Ram N.; Hatch, L. Upton; Clonts, Howard A..
Treatment of time in travel cost models has been a source of contention among economists. The debate persists because welfare estimates, which are the principal objectives of these studies, are highly sensitive to the treatment of time. The present study examines the dual role of on-site time using evidence from two wilderness areas in Alabama. The empirical results comply with the theoretical expectation that on-site time is both a source of utility and cost. The exclusion of on-site time from demand functions results in biased parameter estimates. In particular, it yields smaller own-price coefficients and higher welfare estimates.
Tipo: Journal Article Palavras-chave: Full income; On-site time; Recreation demand; Travel cost model; C24; D60; J20; Q26.
Ano: 2003 URL: http://purl.umn.edu/37857
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The demand for health: differences between the native Dutch and immigrants in the Netherlands AgEcon
Cornelisse-Vermaat, Judith R.; Maassen van den Brink, Henriette.
This paper estimates the demand for health by using a health capital model for different population groups (native Dutch, Surinamese/Antillean, Moroccan, and Turkish) in the Netherlands. Also the effect of overweight on health utility is investigated. We found a decrease in the demand for health for age, overweight, and smoking, we found an increase in the demand for health for level of education and marital status. The analyses show a strong effect of gender. Being female in all groups is negatively related to health utility. Turkish and Moroccan ethnicity is negatively related to health status.
Tipo: Working or Discussion Paper Palavras-chave: Demand for health; Health production; Ethnicity; Overweight; Food habits; Health Economics and Policy; C24; C25; I10; I12.
Ano: 2003 URL: http://purl.umn.edu/46731
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Empirical Evidence Concerning the Finite Sample Performance of EL-Type Structural Equation Estimation and Inference Methods AgEcon
Mittelhammer, Ronald C.; Judge, George G.; Schoenberg, Ron.
This paper presents empirical evidence concerning the finite sample performance of conventional and generalized empirical likelihood-type estimators that utilize instruments in the context of linear structural models characterized by endogenous explanatory variables. There are suggestions in the literature that traditional and non-traditional asymptotically efficient estimators based on moment equations may, for the relatively small sample sizes usually encountered in econometric practice, have relatively large biases and/or variances and provide an inadequate basis for estimation and inference. Given this uncertainty we use a range of data sampling processes and Monte Carlo sampling procedures to accumulate finite sample empirical evidence concerning...
Tipo: Working or Discussion Paper Palavras-chave: Unbiased moment based estimation and inference; Empirical likelihood; Empirical exponential likelihood; Semiparametric models; Conditional estimating equations; Finite sample bias and precision; Squared error loss; Instrumental conditioning variables; Research Methods/ Statistical Methods; C10; C24.
Ano: 2003 URL: http://purl.umn.edu/25090
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Estimating Farm Efficiency in the Presence of Double Heteroscedasticity Using Panel Data AgEcon
Hadri, Kaddour; Guermat, Cherif; Whittaker, Julie.
The accuracy of technical efficiency measures is important given the interest in such measures in policy discussions. In recent years the use of stochastic frontiers has become popular for estimating technical inefficiency, but estimated inefficiencies are sensitive to specification errors. One source of such errors is heteroscedasticity. This paper addresses this issue by extending the Hadri (1999) correction for heteroscedasticity to stochastic production frontiers and to panel data. It is argued that heteroscedasticity within an estimation can have a significant effect on results, and that correcting for heteroscedasticity yields more accurate measures of technical inefficiency. Using panel data on cereal farms, it is found that the usual technical...
Tipo: Journal Article Palavras-chave: Stochastic frontier production; Heteroscedasticity; Technical efficiency; Panel data; Farm Management; Research Methods/ Statistical Methods; C23; C24; D24; Q12.
Ano: 2003 URL: http://purl.umn.edu/43994
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A Semi-Parametric Basis for Combining Estimation Problems Under Quadratic Loss AgEcon
Judge, George G.; Mittelhammer, Ronald C..
When there is uncertainty concerning the appropriate statistical model to use in representing the data sampling process and corresponding estimators, we consider a basis for optimally combining estimation problems. In the context of the multivariate linear statistical model, we consider a semi-parametric Stein-like (SPSL) estimator, ...that shrinks to a random data-dependent vector and, under quadratic loss, has superior performance relative to the conventional least squares estimator. The relationship of the SPSL estimator to the family of Stein estimators is noted and risk dominance extensions between correlated estimators are demonstrated. As an application we consider the problem of a possibly ill-conditioned design matrix and devise...
Tipo: Working or Discussion Paper Palavras-chave: Stein-like shrinkage; Quadratic loss; Ill-conditioned design; Semiparametric estimation and inference; Data dependent shrinkage vector; Asymptotic and finite sample risk.; Research Methods/ Statistical Methods; Cl0; C24.
Ano: 2003 URL: http://purl.umn.edu/25103
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Impacts of Sample Size and Quality-Adjusted Imputed Prices on Own-Price Elasticities Estimated Using Cross-Sectional Data AgEcon
Stockton, Matthew C..
Cross-sectional data sets containing expenditure and quantity information are typically used to calculate quality-adjusted imputed prices. Do sample size and quality adjustment of price statistically alter estimates for own-price elasticities? This paper employs a data set pertaining to three food categories-pork, cheese, and food away from home-with four sample sizes for each food category. Twelve sample sizes were used for both adjusted and unadjusted prices to derive elasticities. No statistical differences were found between own-price elasticities among sample sizes. However, elasticities that were based on adjusted price imputations were significantly different from those that were based on unadjusted prices.
Tipo: Journal Article Palavras-chave: Cross-sectional data; Imputed prices; Quality-adjusted prices; B41; D12; C21; C24.
Ano: 2003 URL: http://purl.umn.edu/43216
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Social Capital and Soil Erosion Control in Agriculturally Marginal Areas of Kenya: The Case of Machakos and Taita-Taveta Districts AgEcon
Obare, Gideon A.; Mwakubo, Samuel M.; Ouma, Emily Awuor; Mohammed, Lutta; Omiti, John M..
This paper evaluates the farmers’ perception of the soil erosion problem, and identifies and analyses social capital elements that motivate households to actively participate in soil conservation in agricultural production process. The data used in the study was generated using a structured questionnaire in a survey that covered 321 households in Kenya’s semi arid districts of Machakos and Taita-Taveta Districts. Two modelling strategies were used: A Probit model was used to estimate the likelihoods of factors that may influence farmers’ perception of soil erosion problem, and a Tobit to estimate parameters of factors that influence terracing intensity. The results indicate that although perception of the soil erosion problem is relatively high in the...
Tipo: Conference Paper or Presentation Palavras-chave: Social capital; Marginal areas; Soil erosion; Perception; Two-step estimation; Kenya; Research and Development/Tech Change/Emerging Technologies; C24; D23; Q15; Z13.
Ano: 2004 URL: http://purl.umn.edu/9532
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Estimating the Link Function in Multinomial Response Models under Endogeneity and Quadratic Loss AgEcon
Judge, George G.; Mittelhammer, Ronald C..
This paper considers estimation and inference for the multinomial response model in the case where endogenous variables are arguments of the unknown link function. Semiparametric estimators are proposed that avoid the parametric assumptions underlying the likelihood approach as well as the loss of precision when using nonparametric estimation. A data based shrinkage estimator that seeks an optimal combination of estimators and results in superior risk performance under quadratic loss is also developed.
Tipo: Working or Discussion Paper Palavras-chave: Multinomial Process; Endogeneity; Empirical likelihood procedures; Quadratic loss; Semiparametric estimation and inference; Data dependent shrinkage; Asymptotic and finite sample risk; Research Methods/ Statistical Methods; C10; C24.
Ano: 2004 URL: http://purl.umn.edu/25095
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COST EFFICIENCY OF CATFISH FARMS IN CHICOT COUNTY, ARKANSAS: THE IMPACT OF EXTENSION SERVICES AgEcon
Engle, Carole R.; Kaliba, Aloyce R..
Cost efficiency measures of a sample of catfish farms in Chicot County, Arkansas are estimated using a data envelopment analysis technique. A measure of overall efficiency is used to determine operator's characteristics, farm practices, and institutional support services that are likely to lead to higher farm level cost efficiency. Results indicate that live catfish production could increase by 55% using the same level of inputs if all farms were operating at the minimum average cost curve. Higher feeding rate and availability of extension services were associated with increased cost efficiency. Higher stocking density affected overall efficiency negatively. The marginal value of extension contacts in Chicot County was estimated to be $2988. This study...
Tipo: Conference Paper or Presentation Palavras-chave: Catfish; Cost efficiency; Data envelopment analysis; And extension services; Resource /Energy Economics and Policy; C14; C24; D61.
Ano: 2004 URL: http://purl.umn.edu/34740
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Measurement and Political Economy of Disputed Technical Regulations AgEcon
Thornsbury, Suzanne; Roberts, Donna; Orden, David.
Technical regulations are increasingly visible in agricultural trade, yet their idiosyncratic nature has limited prior aggregate analysis. This article draws on a unique data source for systematic enumeration of the technical regulations questioned by one exporter among all of its trading partners in mid-1996. Political economy analysis indicates that barriers decrease when the relative contribution of agriculture to an economy increases, when the anticipated future level of protection through other forms of government intervention increases, and when economies are more open. Despite increased scrutiny and discipline by the World Trade Organization, technical barriers remain a significant impediment in world agricultural markets.
Tipo: Journal Article Palavras-chave: Limited dependent variable; Sanitary; And phytosanitary; WTO; F13; F14; C21; C24.
Ano: 2004 URL: http://purl.umn.edu/43448
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Consumer Surplus Estimates and the Source of Regression Error AgEcon
Beatty, Timothy K.M.; Brozovic, Nicholas; Ward, Michael B..
Contrary to widely held belief, we show that the source of regression error does not matter when calculating Marshallian surplus. A misspecified demand curve, not the assumed source of regression error, leads to differences in estimates of consumer surplus.
Tipo: Conference Paper or Presentation Palavras-chave: Regression Error; Marshallian Surplus; Welfare Analysis; Consumer/Household Economics; D60; C24; Q51.
Ano: 2005 URL: http://purl.umn.edu/19477
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EU policy reform simulation based on panel data estimation of on- and off-farm labour supply equations for Dutch dairy farmers AgEcon
Ooms, Daan L.; Hall, Alastair R..
This research focuses on the estimation of labour supply equations for Dutch dairy farmers that are suitable for policy simulations. Data availability leads to the fact that we can not estimate structural labour supply equations. We show how to derive reduced form equations suitable for policy simulations. In this research we use the panel data sample selection estimation approach of Kyriazidou (1997) and Wooldridge (1995) to estimate the off-farm labour supply equation. The two lead to different estimation results and different simulation results based on these.
Tipo: Conference Paper or Presentation Palavras-chave: Econometrics; Panel Data; Sample Selection; Labour Supply; CAP Reform; Labor and Human Capital; C23; C24; C51; C53; D13; J22; Q12; Q18.
Ano: 2005 URL: http://purl.umn.edu/19434
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Precaution and Protectionism: GM Food and the WTO AgEcon
Rigby, Dan; Burton, Michael P.; Young, Trevor.
The dispute between the US and EU over GM foods at the WTO is examined in terms of the issues it raises about protectionism and environmental protection and precaution. The issue of whether GM, GM Derived and Non-GM foods are equivalent to each other is examined using data from a national choice modelling study in the UK. These categories of food are critical since they underpin the EU's new food labelling regime which it hoped would defuse the WTO dispute. The results are analysed using a Bayesian mixed logit model which allows greater flexibility in the modelling of preference distributions. This is particularly crucial where, as in this case, bi-modal distributions are identified with some indifferent or mildly averse to GM foodtypes while others are...
Tipo: Conference Paper or Presentation Palavras-chave: GM food; Mixed logit; WTP; Bayesian; WTO; International Relations/Trade; C11; C24; C25; D12; Q18.
Ano: 2005 URL: http://purl.umn.edu/24447
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Technical, Allocative, and Economic Efficiency in Swedish Dairy Farms: The Data Envelopment Analysis Versus the Stochastic Frontier Approach AgEcon
Johansson, Helena.
Technical, allocative, and economic input efficiency scores were estimated for an unbalanced panel of Swedish dairy farms, using data envelopment analysis (DEA) and the stochastic frontier approach (SFA). By comparing the results it was concluded that when the entire dairy farm is studied the DEA is more appropriate to use since it does not require any particular parametric form to be chosen. The average DEA technical, allocative and economic efficiency indices were eventually found to be 0.77, 0.57, and 0.43 respectively. The influence of size on the efficiency scores was analyzed and significant evidence indicating a positive relationship between size and efficiency was found. Finally it was concluded that the main challenge facing the Swedish dairy...
Tipo: Conference Paper or Presentation Palavras-chave: Technical efficiency; Allocative efficiency; Economic efficiency; Data envelopment analysis; Stochastic frontier approach; Livestock Production/Industries; C14; C23; C24.
Ano: 2005 URL: http://purl.umn.edu/24478
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Incorporating Uncertainty and Cero Values into the Valuation of Protected Areas and Species AgEcon
Hurle, Jesus Barreiro; Garcia, Jose Maria Casada; Perez y Perez, Luis.
Under the Spanish conservation law, compensation is envisaged for the damage associated with all actions that reduce the quantity or quality of protected areas and species. This paper provides a tool to evaluate the monetary equivalent of this damage. We conduct a contingent valuation exercise to estimate the existence value related to protected areas and species in Aragon. This estimate is then reconsidered including the possibility of zero bids and also the possibility of uncertain preferences for non-familiar goods. Considering these two effects, mean values are reduced significantly giving support to previous recommendations of dividing by two contingent valuation estimates from dichotomous choice question formats.
Tipo: Conference Paper or Presentation Palavras-chave: Natural heritage; Contingent valuation; Spike model; Uncertainty; Land Economics/Use; B23; C24; C42; C52; D62; Q26.
Ano: 2005 URL: http://purl.umn.edu/24745
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On- and Off-Farm Labour Supply of Dutch Dairy Farmers: Estimation and Policy Simulations AgEcon
Ooms, Daan L.; Hall, Alastair R..
This research focuses on the effect of decoupled payments on labour supply of Dutch dairy farmers. Data availability leads to the fact that we can not estimate structural labour supply equations. We show how to derive reduced form equations suitable for policy simulations. We use the panel data sample selection estimation approach Wooldridge (1995) to estimate the off-farm labour supply equation. This method is based on Mundlak's (1978) linear panel data estimation approach, which we use to estimate the on-farm labour supply equations. Even though, simulations show a significant negative effect of decoupled payments on labour supply, the economic significance of this effect is very limited.
Tipo: Conference Paper or Presentation Palavras-chave: Decoupled payments; Labour supply; Panel data; Sample selection; Policy simulation; Labor and Human Capital; Livestock Production/Industries; C23; C24; C51; C53; D13; J22; Q12; Q18.
Ano: 2005 URL: http://purl.umn.edu/24506
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Censored Probit Estimation with Correlation near the Boundary: A Useful Reparameteriztion AgEcon
Terza, Joseph V.; Tsai, Wei-Der.
The conventional computational algorithms for full information maximum likelihood (FIML) estimation of the censored probit model (see Farber, 1983), will sometimes fail to converge when the estimated value of the correlation coefficient (ñ) approaches ±1; even when the true value of ñ is not at a boundary. We show that a simple reparametrization of the censored probit model may afford straightforward Newton-Raphson convergence to the true FIML estimate for cases in which likelihood maximization under the conventional censored probit parameterization would have failed. Moreover, our method avoids the computational and inferential complications that arise in alternative methods that, based on a specified criterion, suggest fixing the estimated value of ñ at...
Tipo: Journal Article Palavras-chave: Sample selection; Endogenous treatment effects; Endogenous switching; Qualitative dependent variables; Informal elderly care; Research Methods/ Statistical Methods; I12; C24; C63.
Ano: 2006 URL: http://purl.umn.edu/50278
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Determinants of Malaysian Household Expenditures on Food-Away-From-Home AgEcon
Lee, Helen; Tan, Andrew K.G..
The censored Tobit model is applied on data from the Malaysian Household Expenditure Survey (1998/99) to identify socio-demographic determinants of household expenditures on food-away-from-home (FAFH). Results indicate that Chinese, urban residents, and those with higher monthly household income spend significantly more on FAFH expenditures than their non-Chinese, rural, and lower household income cohorts, ceteris paribus. Other results obtained suggest that age of household head, gender, education level and household size do not significantly affect household expenditures on FAFH. Based on the above findings, several observations are noted. First, the current range of menus being served can be further diversified in order to attract those with religious...
Tipo: Conference Paper or Presentation Palavras-chave: Censored demand; Household-expenditures; Food-away-from-home; Malaysia; Socio-demographics; Food Consumption/Nutrition/Food Safety; L66; C24; D12.
Ano: 2006 URL: http://purl.umn.edu/25430
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