This thesis concerns the development, estimation and investigation of a general anisotropic spatial correlation function, within model-based geostatistics, expressed as a Gaussian linear mixed model, and estimated using residual maximum likelihood (REML). The Matern correlation function is attractive because of its parameter which controls smoothness of the spatial process, and which can be estimated from the data. This function is combined with geometric anisotropy, with an extension permitting different distance metrics, forming a flexible spatial covariance model which incorporates as special cases many infinite- range spatial covariance functions in common use. Derivatives of the residual log-likelihood with respect to the four correlation-model parameters are derived, and the REML algorithm coded in Splus for testing and refinement as a precursor to its implementation into the software ASReml, with additional generality of linear mixed models. Suggestions are given regarding initial values for the estimation. A residual likelihood ratio test for anisotropy is also developed and investigated. Application to three soil-based examples reveals that anisotropy does occur in practice, and that this technique is able to fit covariance models previously unavailable or inaccessible. Simulations of isotropic and anisotropic data with and without a nugget effect reveal the following principal points. Inclusion of some closely-spaced locations greatly improves estimation, particularly of the Matern smoothness parameter, and of the nugget variance when present. The presence of geometric anisotropy does not adversely affect parameter estimation. Presence of a nugget effect introduces greater uncertainty into the parameter estimates, most dramatically for the smoothness parameter, and also increases the chance of non-convergence and decreases the power of the test for anisotropy. Estimation is more difficult with very “unsmooth" processes (Matern smoothness parameter 0.1 or 0.25) | non- convergence is more likely and estimates are less precise and/or more biased. However it is still often possible to fit the full model including both anisotropy and nugget effect using REML with as few as 100 observations. Additional simulations involving model misspecification reveal that ignoring anisotropy when it is present can substantially increase the mean squared error of prediction, but overfitting by attempting to model anisotropy when it is absent is less damaging. Further, plug-in estimates of prediction error variance are reasonable estimates of the actual mean squared error of prediction, regardless of the model fitted, weakening the argument requiring Bayesian approaches to properly allow for uncertainty in the parameter estimates when estimating prediction error variance. The most valuable outcome of this research is the implementation of an anisotropic Matern correlation function in ASReml, including the full generality of Gaussian linear mixed models which permits additional fixed and random effects, making publicly available the facility to fit, via REML estimation, a much wider range of variance models than has previously been readily accessible. This greatly increases the probability and ease with which a well-fitting covariance model can be found for a spatial data set, thus contributing to improved geostatistical spatial analysis. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1297562 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2007

Diss. (sammanfattning) Linköping : Univ., 2003. / Härtill 4 uppsatser.

Made available in DSpace on 2015-07-22T20:49:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Objetivo: Identificar os padrões alimentares de adolescentes eutróficos e com excesso de peso. Métodos: Estudo transversal envolvendo 239 adolescentes de uma escola pública da cidade de São Paulo/SP, Brasil, de ambos os sexos, na faixa etária de 14 a 19 anos. Foram coletados dados antropométricos e registro alimentar de 4 dias. O estado nutricional foi avaliado pelo IMC, de acordo com os critérios de Must et al. Foi aplicada análise fatorial para a identificação dos padrões alimentares. Resultados: Foram identificados 4 padrões alimentares: Tradicional, Urbano, Saudável e Junk Food. O estado nutricional de eutrofia teve associação positiva com os padrões Tradicional e Urbano, o sobrepeso com os padrões Saudável e Junk Food e a obesidade associou-se negativamente com os Padrões Urbano, Saudável e Junk Food. Conclusão: O padrão saudável foi encontrado entre os adolescentes com sobrepeso, evidenciando preocupação com o controle do peso e tentativa de mudança do hábito alimentar. Entre os obesos, a ocorrência do subrelato, provavelmente, influenciou o resultado das associações. / Objective: Identify the dietary patterns of adolescents, both normal and overweight. Method: cross-sectional study of 239 adolescents from a public school in São Paulo/SP, Brazil; of both sexes, aged 14 to 19 years. Anthropometric data was collected and 4-day dietary records were collected. Nutritional status was assessed by BMI, according to the criteria of Must et al. A factor analysis was applied to identify dietary patterns. Results: Out of this assessment, four dietary patterns were identified: Traditional, Urban, Healthy, and Junk Food. The nutritional status of normal weight was positively associated with the Traditional and Urban patterns, the overweight was positively associated with the Healthy and Junk Food patterns, and, lastly, obesity was negatively associated with the Urban, Healthy and Junk Food patterns. Conclusion: The Healthy pattern was found among overweight adolescents, showing concern for weight control and an attempt to change eating habits. Among the obese, the occurrence of underreporting probably influenced the outcome of the associations. / FAPESP: 03/00415-4 / TEDE / BV UNIFESP: Teses e dissertações

Objetivos: Desenvolver um novo instrumento para avaliar espiritualidade e realizar análises psicométricas de validade e confiabilidade. Métodos: O instrumento foi elaborado através de quatro etapas: fundamentação teórica, investigação sobre definições de espiritualidade na população geral, elaboração da primeira versão por um comitê de especialistas e teste de compreensibilidade. Nas análises psicométricas, o instrumento foi submetido à avaliação de juízes e posteriormente, foi testado em estudantes de medicina (N=85) e em uma população de religiosos (N=85), para cálculo de consistência interna, análise fatorial exploratória e confiabilidade teste-reteste. Resultados: O instrumento desenvolvido, a Escala de Atitudes Relacionadas à Espiritualidade (ARES), apóia-se na compreensão sobre espiritualidade no contexto brasileiro e em bases teóricas. Apresentou análises psicométricas apropriadas: a análise fatorial exploratória apontou uma estrututura unidimensional, o alfa de Cronbach encontrado em cada item foi >= 0,98 e o Coeficiente de Correlação Intraclasse (CCI=0,98) apontou boa reprodutibilidade da escala. Conclusão: ARES é um instrumento unidimensional, desenvolvido em idioma português, que apresentou consistência interna excelente e indicou ser reprodutível na população avaliada. São necessários mais estudos para verificar se ARES é aplicável em amostra com baixa escolaridade e em outros contextos culturais e religiosos. A escala ARES permite operacionalizar o construto espiritualidade em pesquisas quantitativas / Objectives: Develop a new instrument devised to measure spirituality, able to perform psychometric analysis of validity and reliability. Methods: The instrument was elaborated through four processes: theoretical foundation, a population based investigation about possible definitions of spirituality, a first version was achieved by a committee of experts in Spirituality along with a comprehension test. In psychometric analysis, the analysis was evaluated by judges, then tested in a population of medical students (N = 85) and in a religious population (N = 85), in order to calculate internal consistency, exploratory factor analysis (EFA) and reliability, through test-retest. Results: The instrument, ARES, a Spirituality-Related Attitudes Scale, was based on theoretical understandings of spirituality in the Brazilian context. It presented an appropriate psychometric analysis: the EFA indicated a one-dimensional structure, the Cronbach\'s Alpha found each item at >= 0.98 and the Intraclass Correlation Coefficient (ICC = 0.98) indicated good reproducibility of the scale. Conclusion: ARES is a one-dimensional instrument, developed in the Portuguese language, which presented an excellent internal consistency and indicated to be reproducible in the evaluated population. Further studies are needed to verify if ARES is applicable to other population samples, for example, a low SES and other cultural/religious contexts. The ARES scale allows for operationalization of the construct of spirituality in quantitative researches

This term project deals with the classification of 1D gel electrophoresis samples. It describes the theoretical information about gel electrophoresis, various types of errors, processing of the image and its classification using the cluster analysis. One of the main goals is creation of images with the highest quality as possible. A realization of pre-processing and detection of the sample borders is made in the MATLAB environment. And finally, classification of samples is done with subsequent statistical analysis.

Using a forensic imager to produce a copy of the storage is a common practice. Due to the large volumes of the modern disks, the imaging may impose severe time overhead which ultimately delays the investigation process. We proposed automated disk analysis techniques that precisely identify regions on the disk that contain data. We also developed a high performance imager that produces AFFv3 images at rates exceeding 300MB/s. Using multiple disk analysis strategies we can analyze a disk within a few minutes and yet reduce the imaging time of by many hours. Partial AFFv3 images produced by our imager can be analyzed by existing digital forensics tools, which makes our approach to be easily incorporated into the workflow of practicing forensics investigators. The proposed approach renders feasible in the forensic environments where the time is critical constraint, as it provides significant performance boost, which facilitates faster investigation turnaround times and reduces case backlogs.

Human health is a complex and wide-ranging subject far beyond nutrition and physical exercise. Still, these factors have a huge impact on global health by their ability to prevent diseases and thus promote health. Thus, to identify health risks and benefits, it is necessary to reveal the underlying mechanisms of nutrition and exercise, which in many cases follows a complex chain of events. As a consequence, current health research is generating massive amounts of data from anthropometric parameters, genes, proteins, small molecules (metabolites) et cetera, with the intent to understand these mechanisms. For the study of health responses, especially related to physical exercise and nutrition, alterations in small molecules (metabolites) are in most cases immediate and located close to the phenotypic level and could therefore provide early signs of metabolic imbalances. Since there are roughly as many different responses to exercise and nutrients as there are humans, this quest is highly multifaceted and will benefit from an interpretation of treatment effects on a general as well as on an individual level. This thesis involves the application of chemometric methods to the study of global metabolic reactions, i.e. metabolomics, in a strategy coined predictive metabolomics. Via the application of predictive metabolomics an extensive hypothesis-free biological interpretation has been carried out of metabolite patterns in blood, acquired using gas chromatography-mass spectrometry (GC-MS), related to physical exercise, nutrition and diet, all in the context of human health. In addition, the chemometrics methodology have computational benefits concerning the extraction of relevant information from information-rich data as well as for interpreting general treatment effects and individual responses, as exemplified throughout this work. Health concerns all lifestages, thus this thesis presents a strategic framework in combination with comprehensive interpretations of metabolite patterns throughout life. This includes a broad range of human studies revealing metabolic patterns related to the impact of physical exercise, macronutrient modulation and different fitness status in young healthy males, short and long term dietary treatments in overweight post menopausal women as well as metabolic responses related to probiotics treatment and early development in infants. As a result, the studies included in the thesis have revealed metabolic patterns potentially indicative of an anti-catabolic response to macronutrients in the early recovery phase following exercise. Moreover, moderate differences in the metabolome associated with cardiorespiratory fitness level were detected, which could be linked to variation in the inflammatory and antioxidaive defense system. This work also highlighted mechanistic information that could be connected to dietary related weight loss in overweight and obese postmenopausal women in relation to short as well as long term dietary effects based on different macronutrient compositions. Finally, alterations were observed in metabolic profiles in relation to probiotics treatment in the second half of infancy, suggesting possible health benefits of probiotics supplementation at an early age. / Embargo until 2012-06-01

Orientador: Cristiano Torezzan / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-21T20:22:07Z (GMT). No. of bitstreams: 1 Costa_MichellyGuerra_M.pdf: 529315 bytes, checksum: 0d134b8239c73b591005b036b0339e20 (MD5) Previous issue date: 2012 / Resumo: No presente trabalho investigamos as semelhanças entre registros de lançamentos extraídos de jogos reais de basquetebol e sequências aleatórias geradas por algoritmos computacionais. Nosso principal objetivo é comparar o comportamento das sequências de arremessos consecutivos de jogadores ao longo de uma temporada com sequências aleatórias de zeros e uns (sequências de Bernoulli) geradas computacionalmente. Para tanto, foram desenvolvidos algoritmos computacionais específicos para os testes e implementados na plataforma Scilab para análise dos dados. Os testes realizados neste trabalho indicam que, de maneira geral, não existem diferenças estatísticas entre os dois conjuntos de dados considerados. Além de uma breve revisão sobre testes estatísticos e sobre o problema da boa fase no jogo de basquetebol, apresentamos diversos exemplos visando tornar o texto acessível para alunos de graduação ou demais interessados em estatística aplicada, em especial ao esporte / Abstract: In this work we investigate the similarities between records of shots extracted from real basketball games and random sequences generated by computational algorithms. Our goal is to compare the behavior of sequences of consecutive shots of players throughout a season with random sequences of zeros and ones (Bernoulli sequences) generated computationally. For this purpose, computational algorithms have been developed for specific tests and implemented in the Scilab platform. The tests performed in this study indicate that, in general, there are no statistical differences between the two sets of data considered. Besides a brief review of statistical tests and the problem of good stage in the game of basketball, we present several examples in order to make the text accessible to undergraduates or others interested in applied statistics, especially the ones concerning this sport / Mestrado / Matematica / Mestra em Matemática

The diploma thesis focuses on the proposition, implementation and evaluation of marketing research of customer satisfaction at 'Big One Fitness'. It addresses the issue of customer satisfaction, services and a questionnaire as the method of questioning. It also analyses the starting position of the company within the competitive environment. Based on the findings of this research it suggests recommendations to enhance customer satisfaction.

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