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	Provedor de dados AgEcon (4) Autor Maradiaga, David Isaias (4) Pujula, Aude Liliana (4) Dicks, Michael R. (3) Zapata, Hector O. (3) Palavra-chave Production Economics (2) Research Methods/ Statistical Methods (2) Risk and Uncertainty (2) Agricultural Exports (1) BRICS (1) Corn Yields (1) Crop Production/Industries (1) Crop yields (1) Currency Exchange Rate (1) Data Transformations (1) Density estimation (1) International Relations/Trade (1) Kernel (1) Nonparametric (1) Nonstationarity (1) Nonstationary (1) Probability Density Estimation (1) Risk (1) Trade (1) U.S. Dollar (1) Mais... Tipo do documento Conference Paper or Presentation (3) Presentation (1) Ano 2012 (1) 2011 (1) 2010 (2) País United States (4) Idioma Inglês (4)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 4 Primeira ... 1 ... Última A century of crop yield density estimation with perspectives AgEcon Pujula, Aude Liliana; Maradiaga, David Isaias; Zapata, Hector O.; Dicks, Michael R.. Tipo: Conference Paper or Presentation Palavras-chave: Crop Production/Industries. Ano: 2010 URL: http://purl.umn.edu/61909 Contemporary Issues in Estimating Yield Distributions AgEcon Pujula, Aude Liliana; Maradiaga, David Isaias; Dicks, Michael R.. In the research area of crop yield density estimation and in particular in risk analysis, little emphasis has been given to the appropriateness of transformation methods (e.g., removing a linear trend) and how such transformations impact the reliability of the empirical distribution functions and the resulting probability estimates. Similarly, there is little consensus on the impact of environmental variables (e.g., rainfall and temperature) on empirical distributions of yields. Using historical county corn yield data for Arkansas and Louisiana and nonparametric methods, this empirical analysis shed light on the importance of data transformation in crop risk analysis. Results demonstrate that inappropriate data treatment can lead to misestimation of... Tipo: Conference Paper or Presentation Palavras-chave: Probability Density Estimation; Nonparametric; Kernel; Nonstationary; Unit Roots; Data Transformations; Corn Yields; Weather; Production Economics; Research Methods/ Statistical Methods; Risk and Uncertainty. Ano: 2010 URL: http://purl.umn.edu/56527 Exchange Rate Volatility in BRICS Countries AgEcon Maradiaga, David Isaias; Zapata, Hector O.; Pujula, Aude Liliana. This paper measures the impact of bilateral exchange rates, the world agricultural GDP and third-country exchange rate volatilities (Yen/USD and Euro/USD) on the BRICS agricultural exports using a vector autoregressive (VAR) model. Two measures of volatility are used: the standard deviation and the coefficient of variation of the rates of change of the real exchange rates. We found that most variables are integrated of order two except the third-country exchange rate volatilities which are stationary and thus considered as exogenous in the VAR models. The causality between I(2) variables was tested using the modified Wald test introduced by Toda and Yamamoto (1995). We found that both volatilities (Yen/USD and Euro/USD) Granger cause Brazilian agricultural... Tipo: Presentation Palavras-chave: BRICS; Currency Exchange Rate; Volatility; Trade; Agricultural Exports; U.S. Dollar; Risk; International Relations/Trade. Ano: 2012 URL: http://purl.umn.edu/119726 Recent Developments in Unit Root Tests and Historical Crop Yields AgEcon Zapata, Hector O.; Maradiaga, David Isaias; Pujula, Aude Liliana; Dicks, Michael R.. This study conducts an investigation on the application of classical unit-root tests using parametric tests (the augmented Dickey-Fuller, 1979 – ADF), and nonparametric tests (Phillips and Perron, 1988—PP) to corn and soybean yields in the Delta states using county-level data from 1961 to 2009. The main concern of the paper is to assess what would be drawn about nonstationarity in crop yields using these tests versus using modified versions of these tests (Ng and Perron, 2001) that are assumed to solve size and power problems associated with the ADF and PP tests. The investigation focuses on methodological aspects of the classical tests, uncovers the nature of filtered yields often needed prior to density estimation, sheds light on the effect of lag... Tipo: Conference Paper or Presentation Palavras-chave: Crop yields; Nonstationarity; Unit-roots; Density estimation; Production Economics; Research Methods/ Statistical Methods; Risk and Uncertainty. Ano: 2011 URL: http://purl.umn.edu/103871 Registros recuperados: 4 Primeira ... 1 ... Última

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