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Registros recuperados: 29
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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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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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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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Consumer Likelihood to Purchase Chickens with Novel Production Attributes AgEcon
Bernard, John C.; Pesek, John D., Jr.; Pan, Xiqian.
Typical supermarket chickens are produced with novel or controversial attributes. This continues despite contrasting growth in consumer interest in organic and natural foods. This study surveyed Delaware consumers’ likelihood to purchase chicken given different attributes: free range, given antibiotics, irradiated, fed genetically modified (GM) fee, GM chicken, and price. Examining conjoint analysis data with a heteroskedastic two-limit tobit model, GM chicken and other novel attributes were found to lower purchase likelihood significantly. Understanding these results should help the industry meet consumer preferences while aiding its continued expansion to benefit workers and growers across the South.
Tipo: Journal Article Palavras-chave: Antibiotics; Chicken; Conjoint analysis; Genetically modified; Heteroskedastic; Irradiated; Tobit; Consumer/Household Economics; Food Consumption/Nutrition/Food Safety; Q13; D12; C24.
Ano: 2007 URL: http://purl.umn.edu/6058
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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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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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To What Surprises Do Hog Futures Markets Respond? AgEcon
Frank, Julieta; Garcia, Philip; Irwin, Scott H..
We reassess the effect of new information in the Hogs and Pigs Reports (HPR) focusing on announcements’ rationality and alternative surprises. HPR announcements are irrational estimates of final estimates, and market expectations are irrational estimates of HPR numbers. Using the market’s best forecast and incorporating final estimates, we modify conventional information measures. Despite differences as large as 33 cents/cwt in price response, findings suggest there is little to differentiate among surprise measures. Regardless, the message that HPR provides new information to the market is strongly supported. On balance, marketing (breeding) information has a larger effect on short-term (long-term) price changes.
Tipo: Journal Article Palavras-chave: HPR; New information; Rationality; Two-limit tobit; USDA announcements; Agribusiness; Agricultural Finance; C24; Q13.
Ano: 2008 URL: http://purl.umn.edu/45046
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Commercialization of Smallholders: Is Market Participation Enough? AgEcon
Gebremedhin, Berhanu; Jaleta, Moti.
The literature on commercial transformation of smallholders makes little distinction between market orientation (production decision based on market signals) and market participation (sale of output). However, policy implications to enhance commercial transformation of subsistence agriculture drawn from the analysis of the determinants of household market participation alone could be inadequate, if in fact, the determinants of market orientation and market participation are not the same or not consistent with each other. This paper analyzes the determinants of market orientation and market participation in Ethiopia separately and examines if market orientation translates into market participation. Empirical results show that the determinants of market...
Tipo: Journal Article Palavras-chave: Commercialization; Smallholders; Market orientation; Market participation; Marketing; C21; C24; Q12; Q13.
Ano: 2010 URL: http://purl.umn.edu/96159
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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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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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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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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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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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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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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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Stigler's approach to recovering the distribution of first significant digits in natural data sets AgEcon
Lee, Joanne; Cho, Wendy K.; Judge, George G..
In 1881, Newcomb conjectured that the first significant digits (FSDs) of numbers in statistical tables would follow a logarithmic distribution with the digit “1” occurring most often. However, because Newcomb’s proposal was not presented with a theoretical basis, it was not given much attention. Fifty-seven years later, Benford argued for the same principle and showed it was relevant to a large range of data sets, and the logarithmic FSD distribution became known as “Benford’s Law.” In the mid-1940s, Stigler claimed Benford’s Law contained a theoretical inconsistency and supplied an alternative derivation for the distribution of FSDs. In this paper, we examine the theoretical basis of the Stigler distribution and extend his reasoning by incorporating FSD...
Tipo: Working or Discussion Paper Palavras-chave: Benford's law; Stigler's law; Power law; Maximum entropy; Distance measures; Research and Development/Tech Change/Emerging Technologies; Research Methods/ Statistical Methods; C10; C24.
Ano: 2009 URL: http://purl.umn.edu/47000
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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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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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Educational Function of Agriculture and Farm Diversification: Evidence from Dairy Farming Experience Services in Japan AgEcon
Ohe, Yasuo.
To promote multifunctional activity, it is crucial to clarify how jointness is formed in connection with farm structure. This paper examines the relationship between multifunctional activity and farm structure by focusing on the educational function of dairy farming, i.e., farming experience services, in Japan. The main findings were as follows. First, from our conceptual consideration we can say that the educational function is determined by technical and institutional jointness and there is a U-shaped relationship between farm diversification and provision of farming experience services. In addition, the national program aimed at promoting this educational function was effective in enhancing this function. Second, however, from the empirical evaluation...
Tipo: Conference Paper or Presentation Palavras-chave: Multifunctionality; Educational function; Farm diversification; Environmental Economics and Policy; Farm Management; Livestock Production/Industries; Q12; Q26; Q57; C24.
Ano: 2009 URL: http://purl.umn.edu/51557
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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
Registros recuperados: 29
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