78 resultados para Multivariate Statistics
Resumo:
Pós-graduação em Medicina Veterinária - FCAV
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
The landuse is usually an human phenomenon that occurs over the years, due to population increase. The territorial knowledge is needed, and is the first step for environmental planning to implement conservation practices on agricultural production system. This study aimed to develop thematic maps as: hydrography, soil, slope, land use, and subbasins to obtain the main geomorphic morphometric data (physical) of the Córrego Rico Watershed. The techniques of remote sensing and geographic information system were used to elaborate the maps and for calculating the geomorphological data, as area, altitude and length of the drainage net, which were submitted to multivariate statistics. The Córrego Rico Watershed has an area of 563 km2 . The predominant slopes were 3-8%, with 55.3% of the total area; and the main use was sugar cane. The soils that predominate in the area are Oxisols towards the Mogi-Guaçú river mouth and Ultisols at the upstream of the basin.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Multivariate quality control studies applied to Ca(II) and Mg(II) determination by a portable method
Resumo:
A portable or field test method for simultaneous spectrophotometric determination of calcium and magnesium in water using multivariate partial least squares (PLS) calibration methods is proposed. The method is based on the reaction between the analytes and methylthymol blue at pH 11. The spectral information was used as the X-block, and the Ca(II) and Mg(II) concentrations obtained by a reference technique (ICP-AES) were used as the Y-block. Two series of analyses were performed, with a month's difference between them. The first series was used as the calibration set and the second one as the validation set. Multivariate statistical process control (MSPC) techniques, based on statistics from principal component models, were used to study the features and evolution with time of the spectral signals. Signal standardization was used to correct the deviations between series. Method validation was performed by comparing the predictions of the PLS model with the reference Ca(II) and Mg(II) concentrations determined by ICP-AES using the joint interval test for the slope and intercept of the regression line with errors in both axes. (C) 1998 John Wiley & Sons, Ltd.
Resumo:
In this study, we deal with the problem of overdispersion beyond extra zeros for a collection of counts that can be correlated. Poisson, negative binomial, zero-inflated Poisson and zero-inflated negative binomial distributions have been considered. First, we propose a multivariate count model in which all counts follow the same distribution and are correlated. Then we extend this model in a sense that correlated counts may follow different distributions. To accommodate correlation among counts, we have considered correlated random effects for each individual in the mean structure, thus inducing dependency among common observations to an individual. The method is applied to real data to investigate variation in food resources use in a species of marsupial in a locality of the Brazilian Cerrado biome. © 2013 Copyright Taylor and Francis Group, LLC.
Resumo:
The MRMAX chart is a single chart based on the standardized sample means and sample ranges for monitoring the mean vector and the covariance matrix of multivariate processes. User's familiarity with the computation of these statistics is a point in favor of the MRMAX chart. As a single chart, the recently proposed MRMAX chart is very appropriate for supplementary runs rules. In this article, we compare the supplemented MRMAX chart and the synthetic MRMAX chart with the standard MRMAX chart. The supplementary and the synthetic runs rules enhance the performance of the MRMAX chart. © 2013 Elsevier Ltd.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
The polyculture among vegetables is an activity that to have good results, needs a proper planning. Although it often requires more labor, has several advantages over monoculture, among them is that polycultures are generally are more productive, provide with productivity of various plant constituents and a more balanced human diet, contribute to economic return, economic and yield stability, social benefits and farmer's direct participation in decision-making. The objective of this study was to evaluate agroeconomic indices of polycultures derived from the combination of two cultivars of lettuce with two cultivars of rocket in two cultures strip-intercropped with carrot cultivar 'Brasilia' through uni-multivariate approaches in semi-arid Brazil. The experimental design used was of randomized complete blocks with five replications and the treatments arranged in a factorial scheme of 2 x 2. The treatments consisted of the combination of two lettuce cultivars (Baba de Verao and Taina) with two rocket cultivars (Cultivada and Folha Larga) in two cultures associated with carrot cv. Brasilia. hi each block were grown plots with two lettuce cultivars and two rocket cultivars, and carrot in sole crop. In each system was determined the lettuce leaf yield, rocket green mass yield and carrot commercial yield. Agrieconomic indices such as operational cost, gross and net income, monetary advantage, rate of return, profit margin, land equivalent ratio and yield efficiency for DEA were used to measure the efficiency of intercropping systems. In the bicropping of lettuce and rocket associated with carrot cv. 'Brasilia', suggests the use of lettuce cultivar 'Taina' combined with rocket cultivars 'Cultivada' or 'Folha Larga'. It was observed significant effect of lettuce cultivars in the evaluation of polycultures of lettuce, carrot and rocket, with strong expression for the lettuce cultivar 'Taina'. Both uni- and multivariate approaches were effective in the discrimination of the best polycultures. (C) 2011 Elsevier Ltd. All rights reserved.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
A new chart based on sample variances for monitoring the covariance matrix of multivariate processes
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Objective: To study the trends and patterns of exclusive breastfeeding (EBF) for under-6-month-old infants in the city of Bauru, southeastern Brazil.Methods: We compared data from three cross-sectional surveys, using similar methodologies, which were part of a project for monitoring breastfeeding indicators in the state of São Paulo, Brazil. The sample included infants aged 0 to 6 months who attended one of the two rounds of the nationwide infant vaccination campaign in 1999, 2003 and 2006 (respectively: 496, 674 and 509 infants). Descriptive statistics were used to compare the prevalence of EBF according to age (in months) and group of children under 6 months of age. Differences in prevalence were expressed as percentage-points and submitted to statistical analysis (Pearson's chi-square and tendency), and the level of significance was set at p < 0.05. Factors associated with EBF interruption in 2006 were evaluated by univariate and multivariate analyses.Results: An increase in the prevalence of EBF was observed in under-6-month-old infants: 1999-2003, increase of 9.1 percentage-points; 2003-2006, increase of 6.6 percentage-points, resulting in an annual increase rate of 2.3 percentage-points for the first period and 2.2 percentage-points for the second period. Significant inverse association was observed between EBF and the use of pacifiers (prevalence ratio = 2.03; 95% confidence interval 1.44-2.84).Conclusion: EBF prevalence in under-6-month-old infants in the city of Bauru, southeastern Brazil, increased almost threefold over the period studied, from 8.5% in 1999 to 24.2% in 2006, a total increase of 184.7%. The use of pacifiers was the only factor strongly associated with the interruption of EBF.