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Análise, imputação de dados e interfaces computacionais em estudos de séries temporais epidemiológicas / Analysis, data imputation and computer interfaces in time-series epidemiologic studiesWashington Leite Junger 01 April 2008 (has links)
efeitos são frequentemente observados na morbidade e mortalidade por doenças respiratórias e cardiovasculares, câncer de pulmão, diminuição da função respiratória, absenteísmo escolar e problemas relacionados com a gravidez. Estudos também sugerem que os grupos mais suscetíveis são as crianças e os idosos. Esta tese apresenta estudos sobre o efeito da poluição do ar na saúde na saúde na cidade do Rio de Janeiro e aborda aspectos metodológicos sobre a análise de dados e imputação de dados faltantes em séries temporais epidemiológicas. A análise de séries temporais foi usada para estimar o efeito da poluição do ar na mortalidade de pessoas idosas por câncer de pulmão com dados dos anos 2000 e 2001. Este estudo teve como objetivo avaliar se a poluição do ar está associada com antecipação de óbitos de pessoas que já fazem parte de uma população de risco. Outro estudo foi realizado para avaliar o efeito da poluição do ar no baixo peso ao nascer de nascimentos a termo. O desenho deste estudo foi o de corte transversal usando os dados disponíveis no ano de 2002. Em ambos os estudos foram estimados efeitos moderados da poluição do ar. Aspectos metodológicos dos estudos epidemiológicos da poluição do ar na saúde também são abordados na tese. Um método para imputação de dados faltantes é proposto e implementado numa biblioteca para o aplicativo R. A metodologia de imputação é avaliada e comparada com outros métodos frequentemente usados para imputação de séries temporais de concentrações de poluentes atmosféricos por meio de técnicas de simulação. O método proposto apresentou desempenho superior aos tradicionalmente utilizados. Também é realizada uma breve revisão da metodologia usada nos estudos de séries temporais sobre os efeitos da poluição do ar na saúde. Os tópicos abordados na revisão estão implementados numa biblioteca para a análise de dados de séries temporais epidemiológicas no aplicativo estatístico R. O uso da biblioteca é exemplificado com dados
de internações hospitalares de crianças por doenças respiratórias no Rio de Janeiro. Os estudos de cunho metodológico foram desenvolvidos no âmbito do estudo multicêntrico para avaliação dos efeitos da poluição do ar na América Latina o Projeto ESCALA. / Air pollution is a public health problem in major urban areas and its effects are frequently observed in the morbidity and mortality due respiratory and cardiovascular causes, lung
cancer, decreasing in the respiratory function, school absenteeism, and pregnancy outcomes. This thesis presents studies on the effects of air pollution on health in the Rio de Janeiro city and tackle some methodological issues on data analysis and missing data imputation in epidemiologic time series. Daily time series were used to estimate the effect of the air pollution on deaths among the elderly due to lung cancer during 2000 and 2001. The purpose of the study was to evaluate if air pollution is associated with premature deaths of people that already are in risk population. Another study was conducted to assess the relationship between air pollution and low birth weight of singleton full term babies. A crosssectional
design was used on data available during the year 2002. Moderate effects of the air pollution were estimated in both studies. Methodological aspects of epidemiologic studies on air
pollution are also approached. A data imputation method is presented and implemented as library for the statistical package R. The imputation methodology is evaluated and compared
to others often used for data imputation in time series of air pollutant concentrations, through simulation techniques. The proposed method has shown best performance compared to those traditionally used. A brief review on the methodology used in the time series studies on the effects of air pollution on health is also presented. The issues approached in the review are also implemented as a library for the analysis of epidemiologic time series in R. The use of the library is exemplified with the analysis on the data of hospital admissions of children due to respiratory causes in the city of Rio de Janeiro. The methodological studies were carried out under the umbrella of the multi-city study to assess the effects of air pollution on health in the Latin America the ESCALA Project.
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Non-Adaptive and Adaptive Coupling Circuits for Power Line Communication SystemCosta, Luís Guilherme da Silva January 2017 (has links)
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Previous issue date: 2017 / Esta tese de doutorado apresenta, inicialmente, uma revisão sobre acopladores para power line communication (PLC), utilizados para acoplar o sinal dos transceptores PLC à rede de energia elétrica. As questões predominantes para o projeto de acopladores e, consequentemente, os diferentes tipos de acopladores são discutidos. Uma classificação dos acopladores PLC baseada nos tipos de acoplamentos (capacitivo, indutivo, resistivo e por antenas), níveis de tensão, largura de banda de frequência, modos de propagação e números de conexões com a rede de energia elétrica é apresentada. Em seguida, o projeto de circuitos PLC de acoplamento capacitivo não adaptativos, single input single output (SISO) de baixa tensão para aplicações banda larga e banda estreita são discutidos. O acoplador PLC banda estreita é projetado para a banda de frequência de 9 kHz-500 kHz, enquanto os acopladores banda larga são projetados para a banda de frequência de 1.7-50 MHz, 1.7-100 MHz e 1.7-500 MHz. Além disso, discute-se as especificações e o projeto dos protótipos desses circuitos de acoplamento PLC medindo seus parâmetros de espalhamento. A seguir, é discutida a medida da impedância de acesso da rede de energia elétrica de baixa tensão na banda de frequência 2- 500 MHz, visando apresentar prévio conhecimento da impedância de acesso da rede de energia elétrica no Brasil com base em uma campanha de medição realizada em várias instalações em três cidades brasileiras diferentes. Além disso, é proposto um procedimento para obter um modelo estatístico da impedância de acesso na referida faixa de frequência. Com base em uma série de medidas de impedâncias de acesso da rede de energia elétrica e critérios para a escolha de modelos estatísticos, esta tese sugere duas distribuições para modelar as componentes resistência e reatância da impedância de acesso da rede de energia elétrica. Uma vez que, os parâmetros de tais modelos mudam com a frequência e que a impedância de acesso é um processo aleatório no domínio da frequência, um modelo simples para gerar amostras em função desse processo aleatório, que leva em consideração as distribuições sugeridas, é detalhado. Por fim, é proposto um circuito de acoplamento adaptativo PLC, capacitivo, SISO de baixa tensão. Estes circuitos de acoplamento adaptativos usam três diferentes filtros analógicos passa-baixa com diferentes impedâncias de entrada. A impedância de entrada de cada filtro analógico é projetado de acordo com os valores obtidos através da campanha de medição, e a impedância de saída é projetada para 50 Ω. A escolha do filtro analógico que proporciona melhor casamento de impedância com a rede de energia elétrica é obtido por um microcontrolador, que através de um conversor analógico digital, monitora a tensão fornecida por um circuito que mede a potência dos sinais injetados nos acopladores PLC pelos transceptores PLC. A monitoração da potência é realizada continuamente pelo conversor analógico digital do microcontrolador que escolhe qual o filtro analógico proporciona o melhor casamento de impedância com a rede de energia elétrica e comuta os filtros analógicos através de uma chave de analógica conectando os transceptores PLC a rede de energia elétrica através dos acopladores PLC. Além disso, as medições dos valores do parâmetro de espalhamento S11 confirmam que a componente resistiva da impedância de acesso da rede de energia elétrica apresentou melhor casamento de impedância entre 50 Ω e 100 Ω. Por fim, os valores medidos do parâmetro de espalhamento S12 mostram que a atenuação cresce com o aumento da frequência devido ao comportamento indutivo da rede de energia elétrica. / This work outlines a comprehensive review of PLC coupling circuits, which are required
for narrowband and broadband PLC transceivers. Prevailing issues that protract
the design of couplers and consequently subtended the inventions of different types
of couplers are clearly described. Also, it provides a useful classification of PLC
couplers based on the type of physical couplings, voltage levels, frequency bandwidth,
propagation modes and a number of connections. Next, the focus is on the design of
non-adaptive capacitive, SISO and low-voltage (LV) PLC coupling circuits for both
broadband and narrowband applications. The narrowband cover the frequency band
9 kHz-500 kHz, while broadband frequency bands are 1.7-50MHz, 1.7-100MHz and 1.7-
500 MHz. Moreover, it discusses the specification and design of the prototypes of the
PLC coupling circuits measuring their scattering parameters. The access impedance
of Brazilian in-home, broadband and low-voltage electric power grid in the frequency
band 2-500 MHz is taken into account. Based on the use of a measurement setup a
large measurement campaign that was carried out in several facilities in three different
Brazilian cities is discussed. Also, a procedure to obtain a statistical model of the access
impedance in the aforementioned broadband frequency is outlined. Based on a number
of measured access impedances and well-known criteria for choosing statistical models,
two distributions to model the resistance and reactance components of the access
impedance are suggested. Due to the fact that the parameters of such models change
with the frequency and the access impedance is a random process in the frequency
domain, a simple and effective model to generate samples function of such random
process, which takes into account the suggested distributions, is addressed. Finally,
adaptive capacitive, SISO and LV PLC coupling circuits are proposed for broadband
power line communication. These adaptive coupling circuits use three different analog
low-pass filter for impedance matching. This filter is an array of analog low-pass
irregular filters that separate the input and output signal into three analog low-pass
filters, each one matching the impedance between the electric power grid and PLC
transceiver. The input impedance of each filter has a different impedance value, chosen
according to the impedance of the measurement campaign, and the output impedance
is fixed in 50 Ω for all analog low-pass filter. The choice of the analog filter that provides
better impedance matching to the electrical power grid is obtained by a microcontroller,
which through an analog-to-digital converter (ADC), measure the voltage provided
by a circuit that measures the power of the signals injected into the PLC coupling
circuit by the PLC transceivers. The power is continuously measured by an ADC
of the microcontroller which chooses which analog filter provides the best impedance
matching with the electric power grid and switches the analog filters through an analog
switcher connecting the PLC transceivers to the electric power grid through the PLC
coupling circuit. In addition, the measured values of the scattering parameter S11 show
that the best impedance matching occurs when the resistive impedance component of
the access impedance is between 50 Ω and 100 Ω . For the scattering parameter S12
it has been found that the attenuation increases as the frequency increases because of
the inductive behavior of the electric power grid.
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The performance of open-end Brazilian fixed income mutual funds for retail clientsWeintraub, Abraham Bragança de Vasconcellos 30 October 2013 (has links)
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Previous issue date: 2013-10-30 / From a financial perspective, this dissertation analyzes the Brazilian mutual fund industry performance for an average retail client. The most representative funds for the local population, that are the fixed income open-end ones, will be selected and their performance will be measured aiming to answer if clients of this industry obtained a proper return over their investments in the period between August 2010 and August 2013. A proper return will be understood as the preservation of the purchasing power of the individual´s savings, what is achieved with a positive performance of a mutual fund after discounting taxes, administrative fees and inflation. After obtaining an answer for the previous question, this dissertation will explore a possible alternative solution: Tesouro Direto, that is an example of a financial approach that could foster the disintermediation between savings and investments through electronic channels. New electronic platforms, with a broader scope, could be utilized to increase the efficiency of funding productive investments through better remunerating Brazilian savings. Tesouro Direto may point towards a new paradigm.
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EVIDENCE-BASED HEALTH PROMOTION: EXPLORING THE EVOLUTION OF THE EFFECTIVENESS OF SCHOOL-BASED ANTI-BULLYING INTERVENTIONS OVER TIMEChalamandaris, Alexandros-Georgios 09 May 2018 (has links)
The objectives of this thesis were to explore how effectiveness of school-based anti-bullying interventions (SBABI) evolves over time and to assess the possibility to predict the medium-term or long-term effectiveness of SBABIs on the basis of their short-term effectiveness. The first step included a literature review in order to understand the study designs and evaluation techniques that researches used to assess the effectiveness. This literature review described the methodologies based on which researchers collected evidence and concluded on the effectiveness of their SBABIs. In order to address the thesis objectives, a collaborative project was established, named SET-Bullying (“Statistical modelling of the Effectiveness of school based anti-bullying interventions and Time”). The above-mentioned literature review was used to identify potentially eligible studies. After addressing a call for collaboration to the corresponding authors of these studies, this project included data from two of them, the DFE-SHEFFIELD study from United Kingdom and the RESPEKT study from Norway. Both of these studies have used pupil self-reported frequencies on being bullied and bullying others as an effectiveness measure, but using different instruments to elicit this information. Thus, the subsequent step of this thesis was to harmonize the data from these studies using polychoric principal components analysis, in order to be able to perform the same analysis with the data from both studies. The data from both studies were analysed using mixed effect models in order to take into account the hierarchical (i.e. the responses of pupils from the same school may be more correlated with each other as opposed to the responses of pupils from different schools) and the longitudinal structure (i.e. same pupils are more likely to respond in a similar way in the repeated measurements of each studies) of the data. With regard to the primary objective of the thesis, it was observed that effectiveness (where it is observed) may evolve either in a linear fashion or a “delayed effect” may be observed. This refers to a minimal evolution of effectiveness over the first study measurements and a sharper evolution at the later study measurements. This finding is only hypothesis generating at this point. Would this be confirmed in future studies, it will have important implication of the design, implementation and evaluations of SBABIs. About the secondary objective of this thesis, there were some preliminary findings of the possibility to predict the medium-term or long-term effectiveness based on the short-term effectiveness. However, these predictions in some cases seemed to be very variable. Future research should focus on how to make these predictions more accurate in order that this allows for dynamic and adaptable delivery of SBABIs. / Doctorat en Santé Publique / info:eu-repo/semantics/nonPublished
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Prediction with Penalized Logistic Regression : An Application on COVID-19 Patient Gender based on Case Series DataSchwarz, Patrick January 2021 (has links)
The aim of the study was to evaluate dierent types of logistic regression to find the optimal model to predict the gender of hospitalized COVID-19 patients. The models were based on COVID-19 case series data from Pakistan using a set of 18 explanatory variables out of which patient age and BMI were numerical and the rest were categorical variables, expressing symptoms and previous health issues. Compared were a logistic regression using all variables, a logistic regression that used stepwise variable selection with 4 explanatory variables, a logistic Ridge regression model, a logistic Lasso regression model and a logistic Elastic Net regression model. Based on several metrics assessing the goodness of fit of the models and the evaluation of predictive power using the area under the ROC curve the Elastic Net that was only using the Lasso penalty had the best result and was able to predict 82.5% of the test cases correctly.
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Dynamics of Coupled Human-Water Infrastructure Systems Under Water Main Breaks and Water-Rates Increase EventsHamed Zamenian (8781884) 30 April 2020 (has links)
<p>The aging water infrastructure
system in the United States has posed considerable hindrance to policy-makers
as they seek to provide safe, reliable, and clean drinking water for
communities. The deterioration of the physical water infrastructure negatively
affects the economics of water utilities and can lead to increases in water
rates for consumers, so that utilities can recover the financial losses.
However, the dynamics emerging from the interactions among changes in water
service reliability, water-rates, consumer behavior (with respect to water
consumption and willingness to support water-rate changes in response to
changes in water rates, and water utility economics, are still unknown factors
in the management of water infrastructure systems. </p>
<p>The overarching objective of
this dissertation is the creation and demonstration of the dynamics of coupled
human and water infrastructure systems under conditions of water main breaks
and water-rate increases. First, using
water-main break data for a 21-year period from two U.S. cities in the Great
Lakes region, the dissertation demonstrates a methodology to estimate the
system-wide monthly frequency of water main breaks as a function of a number of
explanatory variables. Using a random-parameters negative-binomial approach,
the statistical estimations show that pipe diameters, average pipe age,
distribution of pipe age, pipe material, time of year, and mean monthly
temperature all have a significant impact on monthly water main break
frequencies. The results can assist asset managers in quantifying the effect of
factors may have on the likelihood of water main breaks, as well as in making
cost-effective decisions regarding pipe renewal.</p>
<p>Next, by incorporating
qualitative survey data and using quantitative econometric methods, consumer
behaviors in responses to the water-rate increases, and based on perceptions of
water service reliability and quality in a Midwestern U.S. city was evaluated.
Using a multivariate binary probit approach, the results provide insights as to
how individuals are likely to respond to water-rate increases based on the
reliability of current water services and the quality of the supplied water.
The outputs of the econometric enable utility managers to better understand the
behavior of consumers under different rate conditions and help water utilities
in their long-term and short-term financial analyses.</p>
<p>Finally, the aforementioned two
components are integrated into the interdependency analysis to evaluate the
interactive effects of features of the physical water infrastructure (pipeline
characteristics, water and associated energy losses, and the revenue loss for
water utilities) and the behavior of stakeholders (water utilities and
consumers). The developed hybrid system dynamics and agent-based model examines
interdependencies between the physical water infrastructure, the water utility,
and the water consumers to explore possible emergent behavior patterns of water
users during water rate increases over time. The model is demonstrated over the
2001–2010 period on a case study city with a large water distribution system
that includes 4,000 miles of pipeline and nine water treatment plants serving a
population of 863,000. This model was then verified and validated throughout
the development of simulation models and included the following steps: 1) data
validity, 2) conceptual model validity, 3) computerized model validity, and 4)
operational validity. The results suggest the simulated behavior of the model
was reasonable and the output of the simulation model regrading water main
break frequency, amount of water and associated energy losses, generated
revenue, and payoff periods for implementing proactive maintenance strategies
had the accuracy required for the model’s intended purpose. </p>
<p>The framework developed in this doctoral study can be
applied to different size classifications of cities, as well as different
classifications of utility companies (such as electricity and gas) by updating
the parameters in the model to reflect the characteristics of the
infrastructure system components. The distinctive methodological approach in
this doctoral work could capture the emergent behaviors of human-water
infrastructure interactions such as the impact of increasing water-rates on
residential consumers, the impact of water price elasticity cascading into the
water utility revenue, and the impact of residential consumers’ water
consumption on water utility revenues. In conclusion, the results of this
doctoral research can assist asset managers in understanding their systems,
identify pathways for growing revenue through reducing non-revenue water and
increasing water-rates, and implementing a proactive pipeline asset management
program towards the provision for safe, reliable, and clean drinking water.</p>
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Anelastic Strain Recovery Method for In-situ Stress Measurements: A novel analysis procedure based on Bayesian statistical modeling and application to active fault drilling / 非弾性ひずみ回復測定法による原位置応力測定の高度化研究:べイズ統計モデリングに基づく新規解析手法の構築と活断層掘削への適用Sugimoto, Tatsuhiro 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23176号 / 工博第4820号 / 新制||工||1753(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 林 為人, 教授 福山 英一, 准教授 村田 澄彦 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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Measuring the Effects of Performance Funding on Associate Degree Completion by Students of Color at Two-Year Public Institutions of Higher EducationVasquez-Brooks, Marie E. January 2021 (has links)
No description available.
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Statistical and Machine Learning Approaches For Visualizing and Analyzing Large-Scale Simulation DataHazarika, Subhashis January 2019 (has links)
No description available.
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Locality-Dependent Training and Descriptor Sets for QSAR ModelingHobocienski, Bryan Christopher 21 September 2020 (has links)
No description available.
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