Browsing Teses e dissertações by CNPq Subject "CIENCIAS EXATAS E DA TERRA::PROBABILIDADE E ESTATISTICA"
Now showing items 1-20 of 73
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Contribuições sobre o envelope simulado na análise de diagnóstico em modelos de regressão
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 30/04/2019)The simulated envelope is a diagnostic analysis method used to evaluate the hypothesis about the probability distribution assumed for the response variable in a regression model. In this work, we describe some procedures ... -
Modelos de difusão de inovação em grafos
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 12/04/2019)Areas such as politics, economics and marketing are heavily influential in terms of information diffusion. For this reason, several branches of science have studied such phenomena in order to simulate and understand them ... -
Quantificação em problemas com mudança de domínio
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 17/05/2018)Several machine learning applications use classifiers as a way of quantifying the prevalence of positive class labels in a target dataset, a task named quantification. For instance, a naive way of determining what proportion ... -
Modelos preditivos para LGD
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 04/05/2018)Financial institutions willing to use the advanced Internal Ratings Based (IRB) need to develop methods to estimate the LGD (Loss Given Default) risk component. Proposals for PD (Probability of default) modeling have ... -
Estudo do impacto da escolha do modelo para o controle de overdose na fase I dos ensaios clínicos
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 03/10/2018)Escalation with overdose control proportional hazards is a Bayesian method with overdose control that estimates the maximum tolerated dose (MTD) assuming that the time a patient takes to show toxicity follows the proportional ... -
Dois ensaios sobre precificação de ativos
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 15/04/2016)Find fair (according to some criterion) prices for assets in financial markets is one of the most important pillars of Finance Theory. To accomplish this, the Asset Pricing Theory has a mathematical formulation, based ... -
Modelagem de dados de sistemas reparáveis com fragilidade
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 15/09/2015)The usual models in repairable systems are minimal, perfect and imperfect repair, and, in the literature, the minimum repair model is the most explored. In repairable systems it is common that the same type of components ... -
Hedging no modelo com processo de Poisson composto
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 07/12/2015)The investor, that negotiate assets, is subject to economic risks of any negotiation because there is no certainty regarding the appreciation or depreciation of an asset. Here comes the futures market, where contracts can ... -
Degradation modeling for reliability analysis with time-dependent structure based on the inverse gaussian distribution
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 07/04/2017)Conventional reliability analysis techniques are focused on the occurrence of failures over time. However, in certain situations where the occurrence of failures is tiny or almost null, the estimation of the quantities ... -
Percolação Acessível
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 17/02/2020)We consider the accessibility percolation model on the n-ary tree height the _nite h. The model is de_ned by associating a continuous random variable X_v for each vertex v in the tree. The main issue to consider and ... -
Estudo comparativo de métodos de estimação do modelo de resposta gradual para dados de burnout em enfermeiras
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 27/04/2020)The graded response model is an Item Response Theory (IRT) model where items admit a polytomous response widely known in the literature. The motivation for this study comes from a data set which belongs to the RN4CAST ... -
Comparing two populations using Bayesian Fourier series density estimation
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 12/04/2017)Given two samples from two populations, one could ask how similar the populations are, that is, how close their probability distributions are. For absolutely continuous distributions, one way to measure the proximity of ... -
Contribuições em modelos de regressão com erro de medida multiplicativo
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 04/02/2016)In regression models in which a covariate is measured with error, it is common to use structures that correlate the observed covariate with the true non-observed covariate. Such structures are usually additive or ... -
Modelos de mistura para avaliação de produtos e serviços
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 16/12/2019)The product (or services) evaluation is a necessity in many steps of the development and release of such producs (services). The product evolution and the market share definition are two steps that evolves some kind of ... -
Conditional independence testing, two sample comparison and density estimation using neural networks
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 03/08/2020)Given the vast amount of data available nowadays and the rapid increase of computational processing power, the field of machine learning and the so called algorithmic modeling have seen a recent surge in its popularity and ... -
Modelos de Lévy de atividade infinita
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 12/06/2020)In this work, we present a class of pure jump Lévy processes A, with internal filtration and Itô-Lévy decomposition and we established an explicit forms for martingale representation, main component of our process. ... -
Modelos de riscos competitivos no estudo de evasão discente
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 11/02/2020)Dropout is a problem faced by public and private universities. Therefore, the motivation of this work is to investigate the characteristics of students enrolled in a regular undergraduate course and verify which one is ... -
Métodos de estimação em modelos de efeitos mistos não lineares de caudas pesadas
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 05/12/2019)Parameter estimation in nonlinear mixed-effects models is often challenging. In this thesis, a comparison of estimation methods for these models is proposed under a frequentist approach. In the first study, a comparison ... -
Distribuições discretas zero-modificadas para modelar dados de contagem zeros faltantes
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 24/01/2020)The analysis of count data takes an important place in applied statistics, since many real problems are expressed in terms of counts. Frequently, count data sets have discrepancies in the frequency of the zero observation, ... -
Modeling based on a reparameterized Birnbaum-Saunders distribution for analysis of survival data
(Universidade Federal de São Carlos, UFSCar, Programa Interinstitucional de Pós-Graduação em Estatística - PIPGEs, Câmpus São Carlos, 09/01/2017)In this thesis we propose models based on a reparameterized Birnbaum-Saunder (BS) distribution introduced by Santos-Neto et al. (2012) and Santos-Neto et al. (2014), to analyze survival data. Initially we introduce the ...