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	Provedor de dados AgEcon (6) Infoteca-e (1) Ciência Rural (1) Autor Cox, Nicholas J. (3) CONRADO, M. da S. (1) Figueiredo Filho,Luiz Antonio Silva (1) Hendrickx, John (1) Jann, Ben (1) MOURA, M. F. (1) NOGUEIRA, B. M. (1) REZENDE, S. O. (1) SANTOS, F. F. dos (1) Santos,Natanael Pereira da Silva (1) Sarmento,José Lindenberg Rocha (1) Sena,Luciano Silva (1) Smeeton, Nigel (1) Sousa Júnior,Antonio de (1) Williams, Richard A. (1) Ó,Alan Oliveira do (1) Mais... Palavra-chave Categorical data (8) Research Methods/ Statistical Methods (6) Bar charts (2) Graphics (2) Regression models (2) Alternation (1) Atributos redundantes (1) Attribute selection (1) Benford's law (1) Binary data (1) Catplot (1) Chi-squared (1) Clustering (1) Combinatorial algorithms (1) Complex survey correction (1) Compositional data (1) Conditional distribution (1) Cross-tabulations (1) Cumulative distributions (1) Dados categorizados (1) Mais... Tipo do documento Journal Article (4) Article (2) Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) (1) Info:eu-repo/semantics/article (1) Ano 2017 (1) 2010 (1) 2008 (2) 2006 (1) 2004 (1) 2003 (1) 2002 (1) Mais... País United States (6) Brazil (2) Idioma Inglês (7) Português (1)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 8 Primeira ... 1 ... Última Um modelo para a seleção de n-gramas significativos e não redundantes em tarefas de mineração de textos. Infoteca-e MOURA, M. F.; NOGUEIRA, B. M.; CONRADO, M. da S.; SANTOS, F. F. dos; REZENDE, S. O.. Uma proposta completa para resolver o problema de selecionar automaticamente atributos não redundantes do tipo n-gramas é apresentada neste trabalho. Geralmente, o uso de n-gramas é um requisito para melhorar a interpretação subjetiva dos resultados em tarefas de mineração de textos, nesses casos, eles são estatisticamente gerados e selecionados. Após a seleção, em geral, há a presença de redundâncias, por exemplo, o termo "informática agropecuária" e seus componentes "informática" e "agropecuária". Assim, propõe-se um modelo que envolve a remoção de stopwords estatisticamente identificadas, uma seleção estatística eficiente para os atributos do tipo n-grama e a remoção das redundâncias apresentadas após a seleção. Observa-se, pelos resultados... Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) Palavras-chave: Recuperação da informação; Seleção de atributos; N-gramas; Atributos redundantes; Mineração de textos; Dados categorizados; Text mining.; Attribute selection; Categorical data; N-grams; Redundant attribute; Information retrieval.. Ano: 2010 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/885611 Speaking Stata: Spineplots and their kin AgEcon Cox, Nicholas J.. The term spineplot has been applied over the last decade or so to a type of bar chart used particularly for showing frequencies, proportions, or percentages of two cross-classified categorical variables. The principle is that the areas of rectangular tiles are proportional to the frequencies in the cells of a contingency table. Often both coarse and fine structure are easy to see, including departures from independence. The main idea has, in fact, been rediscovered repeatedly over at least the last 130 years. In its most general form, it has been widely publicized under the name mosaic plots. This column introduces, discusses, and exemplifies a Stata implementation of spineplots. It is noted that a restriction to two variables is more apparent than real,... Tipo: Article Palavras-chave: Spineplots; Mosaic plots; Bar charts; Graphics; Categorical data; Research Methods/ Statistical Methods. Ano: 2008 URL: http://purl.umn.edu/120931 Multinomial goodness–of–fit: Large–sample tests with survey design correction and exact tests for small samples AgEcon Jann, Ben. I introduce the new mgof command to compute distributional tests for discrete (categorical, multinomial) variables. The command supports largesample tests for complex survey designs and exact tests for small samples as well as classic large-sample x2-approximation tests based on Pearson’s X2, the likelihood ratio, or any other statistic from the power-divergence family (Cressie and Read, 1984, Journal of the Royal Statistical Society, Series B (Methodological) 46: 440–464). The complex survey correction is based on the approach by Rao and Scott (1981, Journal of the American Statistical Association 76: 221–230) and parallels the survey design correction used for independence tests in svy: tabulate. mgof computes the exact tests by using Monte Carlo methods... Tipo: Article Palavras-chave: Mgof; Mgofi; Multinomial; Goodness-of-fit; Chi-squared; Categorical data; Exact tests; Monte Carlo; Exhaustive enumeration; Combinatorial algorithms; Complex survey correction; Power-divergence statistic; Kolmogorov–Smirnov; Benford's law; Research Methods/ Statistical Methods. Ano: 2008 URL: http://purl.umn.edu/122584 Do-it-yourself shuffling and the number of runs under randomness AgEcon Smeeton, Nigel; Cox, Nicholas J.. A common class of problem in statistical science is estimating, as a benchmark, the probability of some event under randomness. For example, in a sequence of events in which several outcomes are possible and the length of the sequence and number of outcomes of each type known, the number of runs gives an indication of whether the outcomes are random, clustered, or alternating. This note explains and illustrates a simple method of random shuffling that is often useful. We show how the conditional probability distribution of the number of runs may be derived easily in Stata, thus yielding p-values for testing the null hypothesis that the type of outcome is random. We also compare our direct approach with that using the simulate command. Tipo: Journal Article Palavras-chave: Alternation; Categorical data; Clustering; Conditional distribution; Forvalues; P-value; Permutation; Run; Sequence; Simulate; Simulation; Research Methods/ Statistical Methods. Ano: 2003 URL: http://purl.umn.edu/116095 Review of Regression Models for Categorical Dependent Variables Using Stata by Long and Freese AgEcon Hendrickx, John. This article reviews Regression Models for Categorical Dependent Variables Using Stata by Long and Freese. Tipo: Journal Article Palavras-chave: Categorical data; Regression models; Research Methods/ Statistical Methods. Ano: 2002 URL: http://purl.umn.edu/115954 Review of Regression Models for Categorical Dependent Variables Using Stata, Second Edition, by Long and Freese AgEcon Williams, Richard A.. This article reviews Regression Models for Categorical Dependent Variables Using Stata, Second Edition, by Long and Freese. Tipo: Journal Article Palavras-chave: Categorical data; Regression models; Research Methods/ Statistical Methods. Ano: 2006 URL: http://purl.umn.edu/117578 Speaking Stata: Graphing categorical and compositional data AgEcon Cox, Nicholas J.. A variety of graphs have been devised for categorical and compositional data, ranging from widely familiar to more unusual displays. Both official Stata commands and user-written programs are available. After a stacking trick for binary responses is explained, bar charts and related displays for cross-tabulations are discussed in detail. Tips and tricks are introduced for plotting cumulative distributions of graded (ordinal) data. Triangular plots are explained for three-way compositions, such as three proportions or percentages. Tipo: Journal Article Palavras-chave: Graphics; Categorical data; Binary data; Nominal data; Ordinal data; Grades; Compositional data; Cross-tabulations; Bar charts; Cumulative distributions; Logit scale; Catplot; Tabplot; Tableplot; Distplot; Mylabels; Triplot; Research Methods/ Statistical Methods. Ano: 2004 URL: http://purl.umn.edu/116238 Estimate of genetic parameters for carcass traits and visual scores inmeat sheep using Bayesian inference via threshold and linear models Ciência Rural Figueiredo Filho,Luiz Antonio Silva; Sarmento,José Lindenberg Rocha; Ó,Alan Oliveira do; Santos,Natanael Pereira da Silva; Sena,Luciano Silva; Sousa Júnior,Antonio de. ABSTRACT: The aim of this study was to estimate the variance components and genetic parameters for marbling in the ribeye area (MRA) and body condition score (BCS) using Bayesian inference via mixed linear and threshold animal models. Data were obtained from Santa Ines breed sheep reared in the Brazilian Mid-North region. Analyses considering the Monte Carlo methods were performed with Markov chains from 500000 cycles onward. A 200000-cycle initial burn-in was considered with values taken at every 250 cycles, in a total of 1200 samples. The Monte Carlo Error deviations were low for the means heritability in all chains by both linear and threshold models. Additive variances estimated by threshold model were higher than those estimated by the linear model.... Tipo: Info:eu-repo/semantics/article Palavras-chave: Gibbs sampling; Categorical data; Marble meat; Ultrasound. Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782017000300653 Registros recuperados: 8 Primeira ... 1 ... Última

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