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	Provedor de dados AgEcon (4) Colegio de Postgraduados (2) PAB (1) Autor López Martínez, Laura Elizabeth (2) Andrade,Carlos Alberto de Bastos (1) Bergstrom, John C. (1) Brümmer, Bernhard (1) Contreras-Soto,Rodrigo Ivan (1) Figueiredo,Alex Sandro Torre (1) Guimaraes, Paulo de Freitas (1) Gutierrez, Roberto G. (1) Prehn, Soren (1) Rizzardi,Diego Ary (1) Santana,Rosangela Getirana (1) Sardana, Kavita (1) Scapim,Carlos Alberto (1) Mais... Palavra-chave Overdispersion (7) Count data (2) Datos de conteo (2) Discrete distributions (2) Distribuciones discretas (2) Estadística (2) Generalized likelihood ratio test (2) Maestría (2) Prueba de razón de verosimilitud generalizada (2) Research Methods/ Statistical Methods (2) Sobredispersión (2) Beta binomial (1) Clustering (1) Dirichlet multinomial (1) Environmental Economics and Policy (1) Excess Zeros (1) Fixed-effects negative binomial (1) Frailty (1) Gravity Model (1) Heterogeneity (1) Mais... Tipo do documento Conference Paper or Presentation (2) Journal Article (2) Info:eu-repo/semantics/article (1) Ano 2017 (1) 2011 (2) 2010 (2) 2005 (1) 2002 (1) País United States (4) Mexico (2) Brazil (1) Idioma Inglês (5) Espanhol (2)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 7 Primeira ... 1 ... Última A simple approach to fit the beta-binomial model AgEcon Guimaraes, Paulo de Freitas. In this paper, I show how to estimate the parameters of the beta-binomial distribution and its multivariate generalization, the Dirichlet-multinomial distribution. This approach involves no additional programming, as it relies on an existing Stata command used for overdispersed count panel data. Including covariates to allow for regression models based in these distributions is straightforward. Tipo: Journal Article Palavras-chave: Overdispersion; Beta binomial; Dirichlet multinomial; Fixed-effects negative binomial; Research Methods/ Statistical Methods. Ano: 2005 URL: http://purl.umn.edu/117527 Estimation Issues in Single Commodity Gravity Trade Models AgEcon Prehn, Soren; Brümmer, Bernhard. Recently gravity trade models are applied to disaggregated trade data. Here many zeros are characteristic. In the presence of excess zeros usual Poisson Pseudo Maximum Likelihood (PPML) is still consistent, the variance covariance matrix however is invalid. Correct economic interpretation however requires also the last. So alternative estimators are looked for. Staub & Winkelmann [2010] argue that zeroinflated count data models (i.e. zero-inflated Poisson / Negative Binomial Pseudo Maximum Likelihood (ZIPPML / ZINBPML)) are no alternative since under model misspecification these estimators are inconsistent. Yet zero-inflated Poisson Quasi- Likelihood (PQL) is a reliable alternative. It is consistent even under model misspecifications and beyond that... Tipo: Conference Paper or Presentation Palavras-chave: Gravity Model; Homogeneous Firm Trade Model; Excess Zeros; Overdispersion; Negatively Skewed Distribution; Poisson Quasi Likelihood; Two Part Model; International Relations/Trade. Ano: 2011 URL: http://purl.umn.edu/114776 Generalized mixed linear modeling approach to analyze nodulation in common bean inbred lines PAB Rizzardi,Diego Ary; Contreras-Soto,Rodrigo Ivan; Figueiredo,Alex Sandro Torre; Andrade,Carlos Alberto de Bastos; Santana,Rosangela Getirana; Scapim,Carlos Alberto. Abstract: The objective of this work was to compare distributions for the modeling of the number and dry matter weight of nodules (DWN) of Rhizobium from different inoculants in common bean (Phaseolus vulgaris) inbred lines subjected to nitrogen doses, as well as to identify the best inoculant for those lines. The experiment was carried out in a randomized complete block design, arranged in split-split plots, with three factors - four inbred lines, five nitrogen doses (0, 20, 40, 60, and 80 kg ha-1), and three inoculants (CIAT 899, UFLA 02-100, and peat) - and four replicates. The number of nodules and their dry matter weight were analyzed with the generalized linear mixed modeling approach. The highest number of nodules was obtained with the CIAT 899... Tipo: Info:eu-repo/semantics/article Palavras-chave: Phaseolus vulgaris; Rhizobium; Symbiotic nitrogen fixation; Inoculant; Overdispersion; Underdispersion. Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2017001201178 Modeling Site Specific Heterogeneity in an On-Site Stratified Random Sample of Recreational Demand AgEcon Sardana, Kavita; Bergstrom, John C.. Using estimation of demand for the George Washington/Jefferson National Forest as a case study, it is shown that in a stratified/clustered on-site sample, latent heterogeneity needs to be accounted for twice: first to account for dispersion in the data caused by unobservability of the process that results in low and high frequency visitors in the population, and second to capture unobservable heterogeneity among individuals surveyed at different sites according to a stratified random sample (site specific effects). It is shown that both of the parameters capturing latent heterogeneity are statistically significant. It is therefore claimed in this paper, that the model accounting for site-specific effects is superior to the model without such effects.... Tipo: Conference Paper or Presentation Palavras-chave: Recreational Demand models; Clustering; Subject-specific effects; Truncated Stratified Negative Binomial Model; Overdispersion; Environmental Economics and Policy. Ano: 2011 URL: http://purl.umn.edu/103868 Parametric frailty and shared frailty survival models AgEcon Gutierrez, Roberto G.. Frailty models are the survival data analog to regression models, which account for heterogeneity and random effects. A frailty is a latent multiplicative effect on the hazard function and is assumed to have unit mean and variance θ, which is estimated along with the other model parameters. A frailty model is an heterogeneity model where the frailties are assumed to be individual- or spell-specific. A shared frailty model is a random effects model where the frailties are common (or shared) among groups of individuals or spells and are randomly distributed across groups. Parametric frailty models were made available in Stata with the release of Stata 7, while parametric shared frailty models were made available in a recent series of updates. This article... Tipo: Journal Article Palavras-chave: Parametric survival analysis; Frailty; Random effects; Overdispersion; Heterogeneity; Research Methods/ Statistical Methods. Ano: 2002 URL: http://purl.umn.edu/115948 Una prueba de razón de verosimilitudes para discriminar entre la distribución Poisson, Binomial y Binomial Negativa. Colegio de Postgraduados López Martínez, Laura Elizabeth. En este trabajo se realiza inferencia estadística en la distribución Binomial Negativa Generalizada (BNG) y los modelos que anida, los cuales son Binomial, Binomial Negativa y Poisson. Se aborda el problema de estimación de parámetros en la distribución BNG y se propone una prueba de razón de verosimilitud generalizada para discernir si un conjunto de datos se ajusta en particular al modelo Binomial, Binomial Negativa o Poisson. Además, se estudian las potencias y tamaños de la prueba propuesta. Por otro lado, con la finalidad de ilustrar la metodología propuesta, se presentan algunos ejemplos de datos extraídos de investigaciones previas para ver si la prueba es congruente con los resultados que se tienen. _______________ A LIKELIHOOD RATIO TEST TO... Palavras-chave: Sobredispersión; Distribuciones discretas; Datos de conteo; Prueba de razón de verosimilitud generalizada; Overdispersion; Discrete distributions; Count data; Generalized likelihood ratio test; Maestría; Estadística. Ano: 2010 URL: http://hdl.handle.net/10521/222 Una prueba de razón de verosimilitudes para discriminar entre la distribución Poisson, Binomial y Binomial Negativa. Colegio de Postgraduados López Martínez, Laura Elizabeth. En este trabajo se realiza inferencia estadística en la distribución Binomial Negativa Generalizada (BNG) y los modelos que anida, los cuales son Binomial, Binomial Negativa y Poisson. Se aborda el problema de estimación de parámetros en la distribución BNG y se propone una prueba de razón de verosimilitud generalizada para discernir si un conjunto de datos se ajusta en particular al modelo Binomial, Binomial Negativa o Poisson. Además, se estudian las potencias y tamaños de la prueba propuesta. Por otro lado, con la finalidad de ilustrar la metodología propuesta, se presentan algunos ejemplos de datos extraídos de investigaciones previas para ver si la prueba es congruente con los resultados que se tienen. _______________ A LIKELIHOOD RATIO TEST TO... Palavras-chave: Sobredispersión; Distribuciones discretas; Datos de conteo; Prueba de razón de verosimilitud generalizada; Overdispersion; Discrete distributions; Count data; Generalized likelihood ratio test; Maestría; Estadística. Ano: 2010 URL: http://hdl.handle.net/10521/222 Registros recuperados: 7 Primeira ... 1 ... Última

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