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Registros recuperados: 26
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A NONPARAMETRIC HYPOTHESIS TEST VIA THE BOOTSTRAP RESAMPLING AgEcon
Temel, Tugrul T..
This paper adapts an already existing nonparametric hypothesis test to the bootstrap framework. The test utilizes the nonparametric kernel regression method to estimate a measure of distance between the models stated under the null hypothesis. The bootstraped version of the test allows to approximate errors involved in the asymptotic hypothesis test.
Tipo: Conference Paper or Presentation Palavras-chave: Hypothesis test; The bootstrap; Nonparametric regression; Omitted variables; Research Methods/ Statistical Methods; C12; C14; C15.
Ano: 2001 URL: http://purl.umn.edu/20600
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A Note on Business Cycle Non-Linearity in U. S. Consumption AgEcon
Cook, Steven.
The recently examined durability-asymmetry hypothesis of Cook (1999) is re-evaluated using the diagnostic tests of time deformation proposed by Stock (1987, 1988). An application of these tests to disaggregated data on U.S. consumers’ expenditure provides further support for this hypothesis, with the findings given an economic interpretation in terms of variables evolving at differing speeds over different phases of the business cycle. Additionally, building upon the studies of Cover (1992), Karras (1996) and Rhee and Rich (1995), recent research by Arden et al. (2000) has shown the relaxation of the assumptions of linearity and symmetry typically employed in macroeconometric models to result in monetary policy having clear asymmetric effects on the...
Tipo: Journal Article Palavras-chave: Time deformation; Asymmetry; Non-linearity; Consumers’ expenditure; Consumer/Household Economics; C12; E32.
Ano: 2003 URL: http://purl.umn.edu/43990
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A Trend Deduction Model of Fluctuating Oil Prices AgEcon
Xu, Haiyan; Zhang, ZhongXiang.
Crude oil prices have been fluctuating over time and by a large range. It is the disorganization of oil price series that makes it difficult to deduce the changing trends of oil prices in the middle- and long-terms and predict their price levels in the short-term. Following a price-state classification and state transition analysis of changing oil prices from January 2004 to April 2010, this paper first verifies that the observed crude oil price series during the soaring period follow a Markov Chain. Next, the paper deduces the changing trends of oil prices by the limit probability of a Markov Chain. We then undertake a probability distribution analysis and find that the oil price series have a log-normality distribution. On this basis, we integrate the...
Tipo: Working or Discussion Paper Palavras-chave: Oil Price; Log-normality Distribution; Limit Probability of a Markov Chain; Trend Deduction Model; OPEC; Resource /Energy Economics and Policy; Q41; Q47; C12; C49; F01; O13.
Ano: 2011 URL: http://purl.umn.edu/101300
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Canadian Consumers' Preferences for Food Safety and Agricultural Environment Safety AgEcon
Veeman, Michele M.; Li, Yu.
This project applies statistical models to analyse the relative importance ratings for selected food risk issues given in January 2003 by a representative cross-Canada sample of consumers. Ratings for environmental risks that may be associated with agriculture are also assessed. Results of ordered probit econometric models that analyze the influence of respondent's socio-economic and demographic characteristics on food and environmental risk ratings indicate that these are influenced by gender, age, income, employment and location of residence. Males tended to choose lower risk ratings; residents of Quebec tended to give higher risk ratings to most of the queried food and environmental safety issues. The results suggest that measures of trust in...
Tipo: Report Palavras-chave: Food safety; Environmental risks; Risk perceptions; Quantitative assessment; Food Consumption/Nutrition/Food Safety; C12; D12; I19; Q18.
Ano: 2006 URL: http://purl.umn.edu/91557
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Correction of Measurement Error in Monthly USDA Pig Crop: Generating Alternative Data Series AgEcon
Kim, In Seck; Plain, Ronald L.; Bullock, J. Bruce; Jei, Sang Young.
The imputed pig death loss contained in the reported monthly U.S. Department of Agriculture (USDA) pig crop data over the December 1995–June 2006 period ranged from 24.93% to 12.75%. Clearly, there are substantial measurement errors in the USDA monthly pig crop data. In this paper, we present alternative monthly U.S. pig crop data using the biological production process, which is compatible with prior knowledge of the U.S. hog industry. Alternative pig crop data are applied to a slaughter hog model and tested comparatively to USDA pig crop. Test results reject the validity of USDA pig crop data in favor of the alternative data.
Tipo: Journal Article Palavras-chave: Biological production process; Measurement error; Monthly USDA pig crop data; Pig death loss; Agribusiness; Farm Management; Livestock Production/Industries; Q11; Q13; C12.
Ano: 2008 URL: http://purl.umn.edu/47208
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Determining Optimal Levels of Nitrogen Fertilizer Using Random Parameter Models AgEcon
Tumusiime, Emmanuel; Brorsen, B. Wade; Mosali, Jagadeesh; Johnson, Jim; Locke, James; Biermacher, Jon T..
The parameters of yield response functions can vary by year. Past studies usually assume yield functions are nstochastic ‘‘limited’’ stochastic. In this study, we estimate rye– ryegrass yield functions in which all parameters are random. The three functional forms considered are the linear response plateau, the quadratic, and the Spillman-Mitscherlich. Nonstochastic yield models are rejected in favor of stochastic parameter models. Quadratic functional forms fit the data poorly. Optimal nitrogen application recommendations are calculated for the linear response plateau and Spillman-Mitscherlich. The stochastic models lead to smaller recommended levels of nitrogen, but the economic benefits of using fully stochastic crop yield functions are small because...
Tipo: Journal Article Palavras-chave: Cereal rye–ryegrass; Monte Carlo; Nitrogen; Random parameters; Stochastic plateau; Production Economics; Q10; C12; D24.
Ano: 2011 URL: http://purl.umn.edu/117949
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Does Gibrat's Law Hold Amongst Dairy Farmers in Northern Ireland? AgEcon
Kostov, Philip; Patton, Myles; Moss, Joan E.; McErlean, Seamus.
This paper tests whether the Law of Proportionate Effects (Gibrat, 1931), which states that farms grow at a rate that is independent of their size, holds for the dairy farms in Northern Ireland. Previous studies have tended to concentrate on testing whether the law holds for all farms. The methodology used in this study permits investigation of whether the law holds for some farms or all farms according to their size. The approach used avoids the subjective splitting of samples, which tends to bias results. The finding shows that the Gibrat law does hold except in the case of small farms. This is in accordance with previous findings that Gibrat's law tends to hold when only larger farms are considered, but tends to fail when smaller farms are included in...
Tipo: Conference Paper or Presentation Palavras-chave: Gibrat's law; Quantile regression; Sample selection bias; Integrated Conditional Moments test; Agricultural and Food Policy; C12; C14; O49; Q19.
Ano: 2005 URL: http://purl.umn.edu/24775
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Estimating Willingness to Pay for E10 fuel: a contingent valuation study AgEcon
Bhattacharjee, Sanjoy; Petrolia, Daniel R.; Herndon, Cary W., Jr..
In this study, we measure willingness to pay for E10 fuel by US consumers employing a contingent valuation technique in a simultaneous latent variable equation framework. The simultaneous equation framework helps us to understand the way consumers' perceptions about ethanol are developed and influence their respective buying behavior.
Tipo: Conference Paper or Presentation Palavras-chave: E10 ethanol; Perceptions and economic choice; Latent variable; Random utility models; Institutional and Behavioral Economics; Research and Development/Tech Change/Emerging Technologies; Research Methods/ Statistical Methods; C12; C35; D12.
Ano: 2008 URL: http://purl.umn.edu/6730
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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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Estoque de carbono no solo em sistemas convencional e conservacionistas de cultivo de melão no Polo Jaguaribe-Açu. Infoteca-e
GONDIM, R. S.; CRISOSTOMO, L. A.; MAIA, A. de H. N.; SOUSA, J. A. de; BARROS, V. DA S.; ALMEIDA, A. R. DA C. S..
bitstream/item/165065/1/CLV17016.pdf
Tipo: Capítulo em livro técnico (INFOTECA-E) Palavras-chave: Armazenamento de carbono; C12; Condições climáticas; Decomposição de resíduo; Armazenamento de carbono; C12; Condições climáticas; Decomposição de resíduo.
Ano: 2017 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1076190
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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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Food Protection for Sale AgEcon
Lopez, Rigoberto A.; Matschke, Xenia.
This article tests the Protection for Sale (PFS) model using detailed data from U.S. food processing industries from 1978 to 1992 under alternative import demand specifications. All empirical results support the PFS model predictions and previous empirical work qualitatively. Although welfare weights are very sensitive to import demand specification, a surprising result is that we obtain weights between 2.6 and 3.6 for domestic welfare using import slopes or elasticities derived from domestic demand and supply functions. In contrast, results based on import slopes or elasticities from directly specified import demands (including the Armington model) yield the usual, unrealistically large estimates for the domestic welfare weight. We contend that the latter...
Tipo: Working or Discussion Paper Palavras-chave: Trade protection; Tariffs; Lobbying; Political economy; Food manufacturing; Agricultural and Food Policy; Political Economy; F13; F1; L66; C12.
Ano: 2005 URL: http://purl.umn.edu/25195
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High-Grading in a Quota-Regulated Fishery, with Empirical Evidence from the Icelandic Cod Fishery AgEcon
Kristofersson, Dadi; Rickertsen, Kyrre.
Fishers in quota-regulated fisheries find it to their advantage to discard less valuable fish at sea to increase the value of their catch. A theoretical model describing the high-grading behavior of fishers is presented, and an empirical model is derived as well as a testing strategy to test for high-grading and to estimate the discarded amount of each grade. The model is applied to data for the Icelandic quota regulated cod fishery during the period September 1998 to June 2001. The results indicate that highgrading occurs in the Icelandic cod fishery for both long-line and net vessels. However, the discard rates are small, and the results clearly suggest that the ban on discards in Iceland has effectively dealt with high-grading. The estimated discard...
Tipo: Conference Paper or Presentation Palavras-chave: ITQ's; Highgrading; Empirical estimation; Resource /Energy Economics and Policy; Q21; Q22; C12.
Ano: 2005 URL: http://purl.umn.edu/24722
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International Trade, Productivity Growth, Education and the Wage Differential: A Case Study of Taiwan AgEcon
Chang, Hsiao-chuan.
The cause of changes in the wage differential between skilled and unskilled labor has been an important subject of debate for several decades. International trade and productivity growth are two main causes that have been suggested from large country studies. Recent research proposes that education is another influence. All three causes have been significantly associated with Taiwan’s economic development. This paper attempts to contribute to the literature by investigating the wage differential in Taiwan, a small open economy. A Dynamic Intertemporal General Equilibrium (DIGE) model is used to perform theoretical simulation. An Error Correction Model (ECM) incorporating both short- and long-run effects is employed to accomplish the empirical examination....
Tipo: Journal Article Palavras-chave: Wage differential; Dynamic intertemporal general equilibrium model; Error correction model; International Relations/Trade; Labor and Human Capital; C12; C15; C51; F10; F41; H52; J31.
Ano: 2003 URL: http://purl.umn.edu/44011
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La Zone Méditerranéenne Face à la Pollution de L’air : Une Investigation Econométrique AgEcon
Sebri, Maamar.
La dépollution de la Méditerranée constitue l’un des principaux chapitres portés par la coopération entre les deux rives nord et sud dans le cadre de l’Union Pour la Méditerranée (UPM). L’objectif de ce papier est d’examiner la relation existante entre l’évolution des émissions du dioxyde carbone (CO2) et la croissance économique dans les pays membres de l’UPM. Cette relation est décrite par la Courbe Environnementale de Kuznets (CEK) qui postule une relation en U inversé entre la dégradation de l’environnement et la croissance économique. Le choix de la spécification économétrique et le problème des variables omises figurent parmi les controverses révélées autour de la CEK. Dans un premier temps, ce papier vise à sélectionner un modèle parmi trois...
Tipo: Conference Paper or Presentation Palavras-chave: Union Pour la Méditerranée; Emissions de CO2; Courbe Environnementale de Kuznets; Libre-échange; Données de panel; Tests d’hypothèse non emboîtée.; Environmental Economics and Policy; Q56; C12; C23..
Ano: 2009 URL: http://purl.umn.edu/112751
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Looking for Rational Bubbles in Agricultural Commodity Markets AgEcon
Gutierrez, Luciano.
In this paper, we use a bootstrap methodology to helps us to compute the finite sample probability distribution of the asymptotic tests recently proposed in Phillips et al. (2009b) and Phillips and Yu (2009c). Simulation shows that the bootstrap methodology works well and allows us to identify explosive processes and collapsing bubbles. We apply the bootstrap procedure to the wheat and rough rice commodity prices. We find some evidence of price exuberance for both prices in the 2007-2008 period.
Tipo: Presentation Palavras-chave: Rational Speculative Bubbles; Bootstrap; Unit Root Tests; Commodity Prices.; Marketing; G14; Q14; C12; C15.
Ano: 2011 URL: http://purl.umn.edu/120377
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Modeling Non-Linear Spatial Dynamics: A Family of Spatial STAR Models and an Application to U.S. Economic Growth AgEcon
Pede, Valerien O.; Florax, Raymond J.G.M.; Holt, Matthew T..
This paper investigates non-linearity in spatial processes models and allows for a gradual regime-switching structure in the form of a smooth transition autoregressive process. Until now, applications of the smooth transition autoregressive (STAR) model have been largely confined to the time series context. The paper focuses on extending the non-linear smooth transition perspective to spatial processes models, in which spatial correlation is taken into account through the use of a so-called weights matrix identifying the topology of the spatial system. We start by deriving a non-linearity test for a simple spatial model, in which spatial correlation is only included in the transition function. Next, we propose a non-linearity test for a model that includes...
Tipo: Conference Paper or Presentation Palavras-chave: Spatial econometrics; Non-linearity; Utoregressive smooth transition; Research Methods/ Statistical Methods; C12; C21; C51; O18; R11.
Ano: 2008 URL: http://purl.umn.edu/6518
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Optimal intertemporal investment in Australian agriculture: An empirical investigation AgEcon
Agbola, Frank W..
This paper empirically investigates optimal intertemporal investment behaviour of farmers in Australia. The dynamic investment model is estimated using pooled crosssectional and time-series farm survey data spanning the period 1979-1993. The model captures intertemporal investment behaviour of farmers, including independent and instantaneous adjustment decisions. Empirical test results indicate that labour, capital, sheep numbers and cattle numbers adjust sluggishly towards their long-run equilibrium levels. Results provide empirical evidence to indicate that adjustment problem is characteristic of production in agricultural zones Australia.
Tipo: Journal Article Palavras-chave: Australia; Agricultural zones; Optimal intertemporal investment model; Quaxi-fixity; Adjustment costs; Farm Management; Research Methods/ Statistical Methods; C33; C12; C13; C61.
Ano: 2005 URL: http://purl.umn.edu/44094
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Testing for Complementarity and Substitutability among Multiple Technologies: The Case of U.S. Hog Farms AgEcon
Yu, Li; Hurley, Terrance M.; Kliebenstein, James B.; Orazem, Peter F..
We propose a strategy to identify the complementarity or substitutability among technology bundles. Under the assumption that alternative technologies are independent, we develop a hypothetical distribution of multiple technology adoptions. Differences between the observed distribution of technology choices and the hypothetical distribution can be subjected to statistical tests. Combinations of technologies that occur with greater frequency than would occur under independence are complementary technologies. Combinations that occur with less frequency are substitute technologies. This method is easily applied to simultaneous decisions regarding many technologies. We use the strategy to evaluate multiple technology adoptions on U.S. hog farms. We find that...
Tipo: Working or Discussion Paper Palavras-chave: Agribusiness; Agricultural and Food Policy; Livestock Production/Industries; Research and Development/Tech Change/Emerging Technologies; O33; L25; C12.
Ano: 2008 URL: http://purl.umn.edu/48530
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Testing for Speculative Bubbles in Agricultural Commodity Prices: A Regime Switching Approach AgEcon
Liu, Xiaoliang; Filler, Gunther; Odening, Martin.
The sharp increase in agricultural commodity prices in 2008 and in 2011 has triggered an intensive debate on the causes for these price booms. Speculative bubbles have been quoted as one factor among others for the price peaks. Against this background, our paper contributes to this discussion by implementing a novel test procedure for speculative bubbles which has been suggested in the stock market literature. We use a regime switching regression model to test the hypothesis that agricultural prices are driven by periodically collapsing bubbles. The analysis is conducted for wheat, which is one of the most important crops worldwide. Our results show that the data do not support this particular bubbles hypothesis.
Tipo: Presentation Palavras-chave: Agricultural commodity market; Net convenience yield; Speculative bubbles; Regime switching; Fundamental values.; Risk and Uncertainty; C12; Q13; Q14.
Ano: 2012 URL: http://purl.umn.edu/122554
Registros recuperados: 26
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