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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

A journey across football modelling with application to algorithmic trading

Kharrat, Tarak January 2016 (has links)
In this thesis we study the problem of forecasting the final score of a football match before the game kicks off (pre-match) and show how the derived models can be used to make profit in an algorithmic trading (betting) strategy. The thesis consists of two main parts. The first part discusses the database and a new class of counting processes. The second part describes the football forecasting models. The data part discusses the details of the design, specification and data collection of a comprehensive database containing extensive information on match results and events, players' skills and attributes and betting market prices. The database was created using state of the art web-scraping, text-processing and data-mining techniques. At the time of writing, we have collected data on all games played in the five major European leagues since the 2009-2010 season and on more than 7000 players. The statistical modelling part discusses forecasting models based on a new generation of counting process with flexible inter-arrival time distributions. Several different methods for fast computation of the associated probabilities are derived and compared. The proposed algorithms are implemented in a contributed R package Countr available from the Comprehensive R Archive Network. One of these flexible count distributions, the Weibull count distribution, was used to derive our first forecasting model. Its predictive ability is compared to the models previously suggested in the literature and tested in an algorithmic trading (betting) strategy. The model developed has been shown to perform rather well compared to its competitors. Our second forecasting model uses the same statistical distribution but models the attack and defence strengths of each team at the players level rather than at a team level, as is systematically done in the literature. For this model we make heavy use of the data on the players' attributes discussed in the data part of the thesis. Not only does this model turn out to have a higher predictive power but it also allows us to answer important questions about the 'nature of the game' such as the contribution of the full-backs to the attacking efforts or where would a new team finish in the Premier League.
152

A Bayesian approach for modeling stochastic deterioration

SILVA, Rodrigo Bernardo da 31 January 2010 (has links)
Made available in DSpace on 2014-06-12T17:40:37Z (GMT). No. of bitstreams: 2 arquivo720_1.pdf: 2087569 bytes, checksum: 4e440439e51674690e086dbc501c7a58 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / A modelagem de deterioracão tem estado na vanguarda das analises Bayesianas de confiabilidade. As abordagens mais conhecidas encontradas na literatura para este proposito avaliam o comportamento da medida de confiabilidade ao longo do tempo a luz dos dados empiricos, apenas. No contexto de engenharia de confiabilidade, essas abordagens têm aplicabilidade limitada uma vez que frequentemente lida-se com situacões caracterizadas pela escassez de dados empiricos. Inspirado em estrategias Bayesianas que agregam dados empiricos e opiniões de especialistas na modelagem de medidas de confiabilidade não-dependentes do tempo, este trabalho propõe uma metodologia para lidar com confiabilidade dependente do tempo. A metodologia proposta encapsula conhecidas abordagens Bayesianas, como metodos Bayesianos para combinar dados empiricos e opiniões de especialistas e modelos Bayesianos indexados no tempo, promovendo melhorias sobre eles a fim de encontrar um modelo mais realista para descrever o processo de deterioracão de um determinado componente ou sistema. Os casos a serem discutidos são os tipicamente encontrados na pratica de confiabilidade (por meio de simulacão): avaliacão dos dados sobre tempo de execucão para taxas de falha e a quantidade de deterioracão, dados com base na demanda para probabilidade de falha; e opiniões de especialistas para analise da taxa de falha, quantidade de deterioracão e probabilidade de falha. Estes estudos de caso mostram que o uso de informacões especializadas pode levar a uma reducão da incerteza sobre distribuicões de medidas de confiabilidade, especialmente em situacões em que poucas ou nenhuma falha e observada.
153

Produção de leite e desempenho de ovelhas e cordeiros da raça Bergamácia em três sistemas de manejo /

Serrão, Leila Sílvia, 1979- January 2008 (has links)
Orientador: Edson Ramos Siqueira / Banca: Paulo Francisco Domingues / Banca: João Alberto Negrão / Resumo : Resumo: Delineou-se o presente trabalho com o objetivo de avaliar os efeitos de três sistemas de manejo, com diferentes idades à desmama dos cordeiros (48horas, 30 e 45 dias) sobre a produção, composição do leite e incidência de mastite. Utilizaram-se 68 ovelhas Bergamácia distribuídas em três grupos por ordem de parição e idade. A dieta utilizada para os sistemas foi composta de silagem de sorgo e concentrado, na proporção volumoso: concentrado de (40:60), segundo exigência do NRC (1985). Os sistemas foram denominados de acordo com a idade à desmama dos cordeiros, sendo D48h = desmama às 48 horas após o parto e aleitamento artificial até 45 dias; D30d = desmama aos 30 dias e as ovelhas submetidas à ordenha somente após este período; D45d= desmama aos 45 dias com ordenha simultânea à amamentação. Neste último sistema os cordeiros permaneceram com suas mães em pasto durante 8 horas/dia e foram separados no final da tarde. As ovelhas dos três sistemas foram ordenhadas mecanicamente uma vez ao dia, às 8h 00, com produção de leite mensurada diariamente durante 90 dias para os sistemas D48h e D45d e 60 dias para o sistema D30d. Amostras de leite foram coletadas semanalmente para determinação da composição centesimal e contagem de células somáticas. A produção média total de leite das ovelhas do sistema D48h foi similar às ovelhas do sistema D45d e D30d (28,26; 28,65; 18,79 kg/ovelha/lactação, respectivamente). Nas três primeiras semanas, quando apenas os sistemas D48h e D45d foram avaliados, o teor médio de gordura, proteína e sólidos totais apresentaram-se superiores no D48h quando comparados ao D45d. A contagem de células somáticas foi similar entre os sistemas e apenas na primeira semana de lactação as ovelhas do sistema D45d apresentaram menor CCS em relação as ovelhas do sistema D48h. / Abstract: This work aimed to evaluate the effects of three management systems, with different ages of lambs at weaning (48 hours, 30 and 45 days), on production, and composition of milk e incidence of mastitis. It was used 68 Bergamasca ewes allocated in three groups by order of parturition and age. The diet used for the systems was made up with sorghum silage and concentrate, in the volumous:concentrate ratio of (40:60), according to NRC (1985). Systems were named according to lambs' age at weaning, being D48h = weaning 48 hours after parturition and artificial nursing up to 45 days; D30d = weaning at 30 days of age and sheep submitted to milking only after this period; D45d = weaning at 45 days of age with simultaneous milking. In this latter system, lambs remained with their mothers in pasture during 8 hours/day and were separated in the evening. Sheep from the three systems were mechanically milked once a day, at 8h 00 with milk production measured daily during 90 days for D48h and D45d and 60 days for D30d. Milk samples were collected weekly for determination of centesimal composition and somatic cells counting. The final average milk production D48h ewes were similar for systems D45d and D30d, (28.26, 28.65 and 18.79 kg/ewe/lactation, respectively. In the first three weeks, when only systems D48h and D45d were evaluated, the percentage of milk fat, protein, lactose and total solids were higher in D48h when compared to D45d. Somatic cells counting was similar among systems and at the 1-wk test day the D45d ewe was lower SCC than D48h ewe. / Mestre
154

Análise estatística para dados de contagem longitudinais  na presença de covariáveis: aplicações na área médica / Statistical Analyze For Longitudinal Counting Data in Presence of Covariates: Application in Medical Research

Emilio Augusto Coelho Barros 09 February 2009 (has links)
COELHO-BARROS, E. A. Analise estatstica para dados de contagem longitudinais na presenca de covariaveis: Aplicações na area medica. Dissertação (mestrado) - Faculdade de Medicina de Ribeirão Preto - USP, Ribeirão Preto - SP - Brasil, 2009. Dados de contagem ao longo do tempo na presenca de covariaveis são muito comuns em estudos na area da saude coletiva, por exemplo; numero de doenças que uma pessoa, com alguma caracteristica especifica, adquiriu ao longo de um período de tempo; numero de internações hospitalares em um período de tempo, devido a algum tipo de doença; numero de doadores de orgãos em um período de tempo. Nesse trabalho são apresentados diferentes modelos estatsticos de\\fragilidade\" de Poisson para a analise estatística de dados de contagem longitudinais. Teoricamente, a distribuição de Poisson exige que a media seja igual a variância, quando isto não ocorre tem-se a presenca de uma variabilidade extra-Poisson. Os modelos estatsticos propostos nesta dissertação incorporam a variabilidade extra-Poisson e capturam uma possvel correlação entre as contagens para o mesmo indivduo. Para cada modelo foi feito uma analise Bayesiana Hierarquica considerando os metodos MCMC (Markov Chain Monte Carlo). Utilizando bancos de dados reais, cedidos por pesquisadores auxiliados pelo CEMEQ (Centro de Metodos Quantitativos, USP/FMRP), foram discutidos alguns aspectos de discriminação Bayesiana para a escolha do melhor modelo. Um exemplo de banco de dados reais, discutido na Seção 4 dessa dissertação, que se encaixa na area da saude coletiva, e composto de um estudo prospectivo, aberto e randomizado, realizado em pacientes infectados pelo HIV que procuraram atendimento na Unidade Especial de Terapia de Doencas Infecciosas (UETDI) do Hospital das Clnicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HCFMRP-USP). Os esquemas terapêuticos estudados consistiam em zidovudina e lamivudina, associadas ao efavirenz ou lopinavir. Entre setembro de 2004 e maio de 2006 foram avaliados 66 pacientes, sendo 43 deles includos no estudo. Destes, 39 participantes alcançaram a semana 24 de acompanhamento, enquanto 27 atingiram a semana 48. Os grupos de pacientes apresentavam características basais semelhantes, quanto a idade, sexo, mediana de CD4 e carga viral. O interesse desse experimento e estudar a contagem de CD4 considerando os dois esquemas terapêuticos (efavirenz e lopinavir). / COELHO-BARROS, E. A. Analise estatstica para dados de contagem longitudinais na presenca de covariaveis: Aplicac~oes na area medica. Dissertac~ao (mestrado) - Faculdade de Medicina de Ribeir~ao Preto - USP, Ribeir~ao Preto - SP - Brasil, 2009. Longitudinal counting data in the presence of covariates is very common in many applications, especially considering medical data. In this work we present dierent \\frailty\"models to analyze longitudinal Poisson data in the presence of covariates. These models incorporate the extra-Poisson variability and the possible correlation among the repeated counting data for each individual. A hierarchical Bayesian analysis is introduced for each dierent model considering usual MCMC (Markov Chain Monte Carlo) methods. Considering reals biological data set (obtained from CEMEQ, Medical School of Ribeir~ao Preto, University of S~ao Paulo, Brazil), we also discuss some Bayesian discrimination aspects for the choice of the best model. In Section 4 is considering a data set related to an open prospective and randomized study, considering of HIV infected patients, free of treatments, which entered the Infection Diseases Therapy Special Unit (UETDI) of the Clinical Hospital of the Medical School of Ribeir~ao Preto, University of S~ao Paulo (HCFMRP-USP). The therapeutic treatments consisted of the drugs Zidovudine and Lamivudine, associated to Efavirenz and Lopinavir. The data set was related to 66 patients followed from September, 2004 to may, 2006, from which, 43 were included in the study. The patients groups presented similar basal characteristics in terms of sex, age, CD4 counting median and viral load. The main goal of this study was to compare the CD4 cells counting for the two treatments, based on the drugs Efavirenz and Lopinavir, recently adopted as preferencial for the initial treatment of the disease.
155

Resolução de problemas em análise combinatória: uma abordagem no ensino básico / Problem solving in combinatorial analysis: an approach in basic education

BENIGNO, Make Bruno Silva 06 March 2017 (has links)
Submitted by Daniella Santos (daniella.santos@ufma.br) on 2017-11-23T11:57:53Z No. of bitstreams: 1 MAKEBENIGNO.pdf: 503602 bytes, checksum: 341b1fad0eebf1c68b8ab490776354c0 (MD5) / Made available in DSpace on 2017-11-23T11:57:53Z (GMT). No. of bitstreams: 1 MAKEBENIGNO.pdf: 503602 bytes, checksum: 341b1fad0eebf1c68b8ab490776354c0 (MD5) Previous issue date: 2017-03-06 / This work will present the importance of combinatorial analysis, both in middle school and elementary school. We will list several exemples of problems involving combinatorial analysis and we will see how the subject and matter is charged in Enem and mathematics Olympics. Basic, we present some of the main difficulties of some students and combinatoy, shows how the teacher can teach through the solution of the problems, basic that we will present the situation of mathematical education in Brazil and its packaging of basic education. / Este trabalho tem como objetivo apresentar a importância da análise combinatória, tanto no Ensino Médio como no Ensino Fundamental. Listaremos vários exemplos de problemas envolvendo análise combinatória e veremos como esse assunto é cobrado no ENEM e em olimpíadas de matemática. Além disso, apresentamos algumas das principais dificuldades dos alunos em combinatória, e como o professor poderá ensinar por meio da resolução de problemas, além disso apresentaremos a situação da educação matemática no Brasil e seus impactos no ensino básico.
156

Avaliação dos resultados das contagens de células somáticas obtidas pelo equipamento Ekomilk Scan e suas correlações com outros métodos de análise /

Gonçalves, Ana Carolina Siqueira. January 2014 (has links)
Orientador: Ana Maria Centola Vidal Martins / Coorientador: Luiz Francisco Prata / Coorientador: Luiz Carlos Roma Júnior / Banca: Arlindo Saran Netto / Banca: Luiz Augusto do Amaral / Resumo: O advento de métodos alternativos para CCS se torna ferramenta útil aos produtores para o monitoramento da saúde da glândula mamária e também da produção animal. Dessa forma, o presente estudo objetivou avaliar o equipamento Ekomilk Scan® como alternativa para a contagem de células somáticas no leite, testando sua eficácia e confiabilidade além de compará-lo ao método oficial e de referência. Para isso foram colhidas amostras individuais de leite de vacas de várias idades e diferentes estágios de lactação, na região nordeste do Estado de São Paulo. Foram testadas as variáveis inerentes ao equipamento (repetibilidade e reprodutibilidade), e aquelas possíveis influenciadoras do resultado (uso de conservante, temperatura, tempo entre coleta e análise, raça e composição do leite). As variáveis dependentes foram submetidas à análise de variância através do Sistema SAS e pelo teste dos quadrados mínimos. Os resultados indicaram que o Ekomilk Scan® é um equipamento preciso, pois apresenta resultados concisos quando realizados independentemente porém sob as mesmas condições. Para a realização das análises não se deve acrescentar conservante nas amostras e devem ser realizadas no mesmo dia de coleta apesar da temperatura na qual a amostra se encontra não influenciar significativamente os resultados. Além disso, ao se comparar o Ekomilk Scan® a outros métodos de análise, verificou-se boa correlação dos resultados com a microscopia ótica. Dessa forma, conclui-se que o equipamento testado é preciso e confiável, podendo ser uma boa alternativa no monitoramento da CCS em unidades produtivas / Abstract: The advent of alternative methods for SCC becomes useful tool for producers to monitor the health of the mammary gland and also the livestock. The present study aimed to evaluate the equipment Ekomilk Scan® as an alternative to somatic cell count in milk, testing their effectiveness and reliability as well as compare it to the standard and reference methods. For this were collected individual cow milk samples of various ages and different stages of lactation in northeastern state of São Paulo region. Variables inherent to the equipment (repeatability and reproducibility), and those that are merely influencing the outcome (use of preservative, temperature, time between collection and analysis, breed and milk composition) were tested. The dependent variables were analyzed using the SAS System and the test of least squares. The results indicated that the Ekomilk Scan® is precise and presents concise results when performed independently but under the same conditions. To perform the samples should not add preservative and the analyses should be conducted on the same day of collection despite the temperature at which the sample is not significantly influence the results. Furthermore, when comparing the Ekomilk Scan® to other methods of analysis, that the results showed good correlation with the optical microscope method. Thus, it is concluded that the equipment tested is accurate and reliable and may be a good alternative for monitoring of SCC in production units / Mestre
157

Statistical analysis methods for time varying nanoscale imaging problems

Laitenberger, Oskar 29 June 2018 (has links)
No description available.
158

Imageurs à amplification / Amplified imagers

Gach, Jean-Luc 03 April 2018 (has links)
La quête du détecteur parfait, sans bruit, capable de détecter des photons uniques dans le visible et l’infrarouge, et ultimement de déterminer leur énergie est le graal de la détection. Pour arriver à ce but, de nombreux scientifiques ont développé des dispositifs depuis plusieurs dizaines d’années, et les astronomes ont toujours été à la pointe en ce domaine. En ce sens les imageurs à amplification semblent être la voie la plus rapide et la plus prometteuse pour atteindre ce but ultime. Ainsi après un bref historique de l’état de l’art sont exposés les systèmes à comptage de photons (IPCS) développés au LAM, qui ont été utilisés sur les télescopes ESO 3m60, OHP 1m93 ou encore WHT 4m20. Sont ensuite abordés les dispositifs imageurs intégrés à amplification comme les EMCCD (Electron multiplying charge coupled devices) dans le visible, avec quelques exemples de leur utilisation en astronomie. C’est la technologie qui, appliquée aux senseurs de front d’onde, aura permis conjointement à d’autres développements l’avènement des optiques adaptatives extrêmes comme celle de l’instrument VLT-SPHERE ou encore de SUBARU-SCExAO. Pour finir les e-APD (electron initiated avalanche photodiode) dans l’infrarouge seront abordés. Les e-APD ont cette propriété très intéressante d’être des amplificateurs quasi parfaits, et ont une capacité à détecter l’énergie des photons, des propriétés qui seront développées et analysées. Nous finirons par les perspectives et les progrès que nous sommes en droit d’attendre dans les prochaines années. / The quest for the perfect, noiseless detector, capable of detecting unique photons in the visible and infrared, and ultimately determining their energy is the grail of detection. To achieve this goal, many scientists have developed devices for several decades, and astronomers have always been at the forefront in this area. In this sense amplification imagers seem to be the fastest and most promising way to achieve this ultimate goal. Thus, after a brief history of the state of the art are exposed the photon counting systems (IPCS) developed at LAM, which were used on ESO telescopes 3m60, OHP 1m93 or WHT 4m20. Imaging integrated imaging devices such as Electron Multiplying Charge Coupled Devices (EMCCDs) are then discussed in the visible, with some examples of their use in astronomy. It is the technology that, applied to the wavefront sensors, has jointly enabled other developments the advent of extreme adaptive optics such as the VLT-SPHERE or SUBARU-SCExAO. To finish the e-APD (electron-induced avalanche photodiode) in the infrared will be discussed. E-APDs have this very interesting property of being almost perfect amplifiers, and have an ability to detect photon energy, properties that will be developed and analyzed. We will end up with the prospects and the progress that we are entitled to expect in the coming years.
159

Crime, governance and numbers : a genealogy of counting crime in New South Wales

Johnson, Andrew, University of Western Sydney, Hawkesbury, Faculty of Social Inquiry, School of Ecology January 2000 (has links)
This thesis is an intellectual genealogy of counting crime in New South Wales. It is a history of a system of thought which is one of the contemporary foundations of the way we interpret the nature and extent of crime today. It argues that the incitement to annually record crime statistics in New South Wales, and internationally, is immediately connected with a will to govern crime. This thesis traces this bonding of the technology of crime statistics with mentalities of government, and maintains that although the connection of these two discourses has been highly effective, it has not been one of universal domination. This is a history of the continuous state practice of compiling and publishing crime statistics. But it is also a history of discontinuities. This thesis regularly investigates shifts in the categories of recording. It locates changes in what is recorded by broadening its discussion to include localised and international debates on crime that are contemporaneous to these changes. This is not a thesis with a project to improve the way in which we record or utilise crime statistics. Its project is to write a history of how we came to record crime statistics and how we have intended to utilise these crime statistics in our practices of government. It traces the rise of counting crime and interrogates it as one of the key technologies deployed in the government of crime / Doctor of Philosophy (PhD)
160

Environmental stochasticity and density dependence in animal population models

Samaranayaka, Ari, n/a January 2006 (has links)
Biological management of populations plays an indispensable role in all areas of population biology. In deciding between possible management options, one of the most important pieces of information required by population managers is the likely population status under possible management actions. Population dynamic models are the basic tool used in deriving this information. These models elucidate the complex processes underlying the population dynamics, and address the possible consequences/merits of management actions. These models are needed to guide the population towards desired/chosen management goals, and therefore allow managers to make informed decisions between alternative management actions. The reliability that can be placed on inferences drawn from a model about the fate of a population is undoubtedly dependent on how realistically the model represents the dynamic process of the population. The realistic representation of population characteristics in models has proved to be somewhat of a thorn in the side of population biologists. This thesis focuses in particular on ways to represent environmental stochasticity and density dependence in population models. Various approaches that are used in building environmental stochasticity into population models are reviewed. The most common approach represents the environmental variation by changes to demographic parameters that are assumed to follow a simple statistical distribution. For this purpose, a distribution is often selected on the basis of expert opinion, previous practice, and convenience. This thesis assesses the effect of this subjective choice of distribution on the model predictions, and develops some objective criteria for that selection based on ecological and statistical acceptability. The more commonly used distributions are compared as to their suitability, and some recommendations are made. Density dependence is usually represented in population models by specifying one or more of the vital rates as a function of population density. For a number of reasons, a population-specific function cannot usually be selected based on data. The thesis develops some ecologically-motivated criteria for identifying possible function(s) that could be used for a given population by matching functional properties to population characteristics when they are known. It also identifies a series of properties that should be present in a general function which could be suitable for modelling a population when relevant population characteristics are unknown. The suitability of functions that are commonly chosen for such purposes is assessed on this basis. I also evaluate the effect of the choice of a function on the resulting population trajectories. The case where the density dependence of one demographic rate is influenced by the density dependence of another is considered in some detail, as in some situations it can be modelled with little information in a relatively function-insensitive way. The findings of this research will help in embedding characteristics of animal populations into population dynamics models more realistically. Even though the findings are presented in the context of slow-growing long-lived animal populations, they are more generally applicable in all areas of biological management.

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