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Forecasting Global Equity Indices Using Large Bayesian VARsHuber, Florian, Krisztin, Tamás, Piribauer, Philipp 10 1900 (has links) (PDF)
This paper proposes a large Bayesian Vector Autoregressive (BVAR) model with common stochastic volatility to forecast global equity indices. Using a dataset consisting of monthly data on global stock indices the BVAR model inherently incorporates co-movements in the stock markets. The time-varying specification of the covariance structure moreover accounts for sudden shifts in the level of volatility. In an out-of-sample forecasting application we show that the BVAR model with stochastic volatility significantly outperforms the random walk both in terms of root mean squared errors as well as Bayesian log
predictive scores. The BVAR model without stochastic volatility, on the other hand, underperforms relative to the random walk. In a portfolio allocation exercise we moreover show that it is possible to use the forecasts obtained from our BVAR model with common stochastic volatility to set up simple investment strategies. Our results indicate that these simple investment schemes outperform a naive buy-and-hold strategy. (authors' abstract) / Series: Department of Economics Working Paper Series
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Storm Water Management Using a High Density Rainfall Network Along With Long Term RecordsMokhtarnejad, Siamak N. 19 December 2008 (has links)
The United States Weather Bureau had published Technical Paper No. 40 (TP-40) in 1961 which provides a rainfall atlas for the United States. These rainfall frequencies have been used by engineers throughout the United States including Jefferson Parish, Louisiana. Rainfall from Audubon and the New Orleans International Airport rain gauge stations were used with the Log Pearson Method to provide rainfall frequency for Jefferson Parish, Louisiana. The results from the frequency rainfall that were developed for this research along with the current Jefferson Parish design storm rainfall were applied to a typical urban development to evaluate the extent of flooding.
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Jakten på en positiv scenupplevelse : en självstudie om mental träning / The quest for a positive stage experience : a study on mental trainingJosefsson, Samuel January 2016 (has links)
Syftet med denna självstudie är att utforska på vilka sätt mental träning kan förändra livsvärlden samt minska obehag inför scenframträdanden. Syftet bärs upp av följande forskningsfråga: På vilka sätt förändras livsvärlden genom mental träning inför ett framträdande? Studien utgår från ett livsvärldsperspektiv och metod är loggboksskrivande. Resultatet presenteras med hjälp av teman som: Att öppna medvetandet, Självbildsträning – att tycka om sig själv, Förebilder – att se sig själv, Vad jag vill odla inom mig, Att vara förberedd, Sista förberedelsen och Tiden är inne. Efter resultatet följer en diskussion om vikten av avslappning och en bra självbild samt för- och nackdelar med att använda Fagéus metod i mental träning. Arbetet avslutas med att frågan om dess betydelse vidrörs samt möjligheter till framtida forskning. / The purpose of this study is to explore the ways mental training can alter my life-world and reduce the discomfort I experience during stage performances. The study is supported by the following research question: In which ways does my life-world change through the use of mental training before a performance? The study is based on a life-world perspective and the method for the study is logbook writing. The result is presented by following themes: Opening minds, Self-image Training – enjoying myself, Role models – to see myself, What I want to grow within me, Being prepared, Final preparation and The time has come. After the result follow a discussion of the importance of relaxation and a good self-image, I also discuss the advantages and disadvantages of using Fagéus method of mental training. The work concludes with the questions of the importance of this study and the opportunities for future research.
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Characteristics of the log periodic dipole arrayOnwuegbuna, Leonard Ikemefuna 28 February 2007 (has links)
Student Number : 9713144D -
MSc Dissertation -
School of Electrical Engineering -
Faculty of Engineering and the Built Environment / The performance of the Log Periodic dipole array antenna has been characterized,
in the form of parametric curves available in most antenna design handbooks and
other relevant literature. These characteristic curves are often limiting in scope,
as for instance they do not contain parametric curves giving the relationship
between the boom-length 'L' and the number of dipole element 'N' for any given
bandwidth, even when it is known that these two parameters are the main cost
determinants of a LPDA Antenna. The concept of convergence is introduced to
aid cost optimization of the LPDA Antenna in terms of number of dipole element
'N'. Although 'N' is used as the minimization criterion, the criteria for establishing
convergence encompass all the main electrical characteristics of the LPDA
Antenna, such as VSWR, gain and radiation patterns. Lastly, the effects of boomimpedance
'Zo' and length to diameter ration 'Ln/Dn', on the performance
characteristics of the LPDA Antenna was investigated with the view to
determining if neglecting the effects of these two parameters were responsible for
the disparity in the directive gain values obtained by R. L Carrel compared to
those obtained by later researchers. The investigation indicates that if an LPDA
Antenna is converged, then the effects of Zo and Ln/Dn ratio though significant
can not alone account for the fairly large disparity in the gain values.
In other to perform these investigations, a modern scientific tool in the form of
numerical modeling by method of moments based, Super Numerical
electromagnetic code version2 was utilized. The numerical modeling tool was
first validated by agreement between measured values and the values as predicted
by the modeling tool. Next, simulation of the performance of LPDA antennas
under variations of their number of elements was done. Thereafter, the means and
standard deviations of the gain were extracted from the simulated numerical
models. Trends in the pattern of variation of the means and standard deviations of
the gain are used as the basis for deciding the value of number of element at
which the antenna can yield acceptable performance (convergence criteria). These
are presented as convergence curves, which gives for any given boom-length and operating bandwidth, the minimum number of elements required for the antenna
to yield acceptable performance.
Finally, the effect of length to diameter ratio and boom-impedance on the gain of
optimized LPDA antennas are presented as parametric curves.
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Usage-driven unified model for user profile and data source profile extraction / Model unifié dérigé par l'usage pour l'extraction du profile de l'utilisateur et de la source de donnéeLimam, Lyes 24 June 2014 (has links)
La problématique traitée dans la thèse s’inscrit dans le cadre de l’analyse d’usage dans les systèmes de recherche d’information. En effet, nous nous intéressons à l’utilisateur à travers l’historique de ses requêtes, utilisées comme support d’analyse pour l’extraction d'un profil d’usage. L’objectif est de caractériser l’utilisateur et les sources de données qui interagissent dans un réseau afin de permettre des comparaisons utilisateur-utilisateur, source-source et source-utilisateur. Selon une étude que nous avons menée sur les travaux existants sur les modèles de profilage, nous avons conclu que la grande majorité des contributions sont fortement liés aux applications dans lesquelles ils étaient proposés. En conséquence, les modèles de profils proposés ne sont pas réutilisables et présentent plusieurs faiblesses. Par exemple, ces modèles ne tiennent pas compte de la source de données, ils ne sont pas dotés de mécanismes de traitement sémantique et ils ne tiennent pas compte du passage à l’échelle (en termes de complexité). C'est pourquoi, nous proposons dans cette thèse un modèle d’utilisateur et de source de données basé sur l’analyse d’usage. Les caractéristiques de ce modèle sont les suivantes. Premièrement, il est générique, permettant de représenter à la fois un utilisateur et une source de données. Deuxièmement, il permet de construire le profil de manière implicite à partir de l’historique de requêtes de recherche. Troisièmement, il définit le profil comme un ensemble de centres d’intérêts, chaque intérêt correspondant à un cluster sémantique de mots-clés déterminé par un algorithme de clustering spécifique. Et enfin, dans ce modèle le profil est représenté dans un espace vectoriel. Les différents composants du modèle sont organisés sous la forme d’un Framework, la complexité de chaque composant y est évaluée. Le Framework propose : - une méthode pour la désambigüisation de requêtes; - une méthode pour la représentation sémantique des logs sous la forme d’une taxonomie ; - un algorithme de clustering qui permet l’identification rapide et efficace des centres d’intérêt représentés par des clusters sémantiques de mots clés ; - une méthode pour le calcul du profil de l’utilisateur et du profil de la source de données à partir du modèle générique. Le Framework proposé permet d'effectuer différentes tâches liées à la structuration d’un environnement distribué d’un point de vue usage. Comme exemples d’application, le Framework est utilisé pour la découverte de communautés d’utilisateurs et la catégorisation de sources de données. Pour la validation du Framework, une série d’expérimentations est menée en utilisant des logs du moteur de recherche AOL-search, qui ont démontrées l’efficacité de la désambigüisation sur des requêtes courtes, et qui ont permis d’identification de la relation entre le clustering basé sur une fonction de qualité et le clustering basé sur la structure. / This thesis addresses a problem related to usage analysis in information retrieval systems. Indeed, we exploit the history of search queries as support of analysis to extract a profile model. The objective is to characterize the user and the data source that interact in a system to allow different types of comparison (user-to-user, source-to-source, user-to-source). According to the study we conducted on the work done on profile model, we concluded that the large majority of the contributions are strongly related to the applications within they are proposed. As a result, the proposed profile models are not reusable and suffer from several weaknesses. For instance, these models do not consider the data source, they lack of semantic mechanisms and they do not deal with scalability (in terms of complexity). Therefore, we propose a generic model of user and data source profiles. The characteristics of this model are the following. First, it is generic, being able to represent both the user and the data source. Second, it enables to construct the profiles in an implicit way based on histories of search queries. Third, it defines the profile as a set of topics of interest, each topic corresponding to a semantic cluster of keywords extracted by a specific clustering algorithm. Finally, the profile is represented according to the vector space model. The model is composed of several components organized in the form of a framework, in which we assessed the complexity of each component. The main components of the framework are: - a method for keyword queries disambiguation; - a method for semantically representing search query logs in the form of a taxonomy; - a clustering algorithm that allows fast and efficient identification of topics of interest as semantic clusters of keywords; - a method to identify user and data source profiles according to the generic model. This framework enables in particular to perform various tasks related to usage-based structuration of a distributed environment. As an example of application, the framework is used to the discovery of user communities, and the categorization of data sources. To validate the proposed framework, we conduct a series of experiments on real logs from the search engine AOL search, which demonstrate the efficiency of the disambiguation method in short queries, and show the relation between the quality based clustering and the structure based clustering.
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Projektering av takkonstruktioner med förindustriella träförband : beräkning och provning av hophuggningarRöjerås, Anders January 2019 (has links)
In earlier wood constructions, the method of joining the parts was by the carpenter joint. There are many different kinds of carpenter joints. The kind of carpenter joint that was used was partly due to the type of building, but also to local variations in building tradition. The industrialization at the end of the 19thcentury led to new construction technology with new types of joints. It gradually became more difficult for the craftsmen to compete with mass-produced standard joints with screws and nails. During the latter half of the 20thcentury, it once again began to become popular with the carpenter joint. New technology in the wood industry began to make carpenter joints competitive. Modern technology with modeling of geometries has made it possible to analyze and optimize structures and joints in a new way. Verification through tests has also led to increased understanding of wood joints. Calculation of the load bearing capacity in carpenter joints is possible by applying calculation rules in Eurocode. The purpose with this study is to verify strength calculations for a traditional carpenter joint. An analysis of an imagined timber frame and roof truss was made in a calculation program to assess in a rough manner what section forces the structure was subjected to. A dovetail joint in the roof truss shown in fig. 1 was chosen for further analysis. Manual calculation of the load bearing capacity in the dovetail joint was made. Verification of the calculations was then done through strength tests in a lab. The study shows that it is possible to calculate the load bearing capacity in a dovetail joint and that account must be taken to eccentricities in the joint and varying wood quality. / I äldre träbärverk var metoden för sammanfogning av virkesdelar hophuggningen. Det finns en mängd olika typer av hophuggningar. Vilken typ av hophuggning som användes berodde dels på byggnadstypen men även på lokala variationer i byggnadstradition. Industrialiseringen under slutet på 1800-talet bidrog till ny byggteknik med nya typer av förband. Det blev efter hand svårare för timmermännen att konkurrera med massproducerade standardförband med skruv och spik. Under senare halvan av 1900-talet började det åter bli populärt med hophuggningen. Ny teknik inom träindustrin började åter göra timmerförband konkurrenskraftiga. Modern teknik med modellering av geometrier har även gjort det möjligt att på ett nytt sätt analysera och optimera bärverk och förband. Verifiering genom tester har också lett till ökad förståelse av timmerförband. Beräkning av bärförmågan i hophuggningar är möjligt genom tillämpning av beräkningsregler i Eurokod. Syftet med detta arbete är att verifiera hållfasthetsberäkningar för ett traditionellt timmerförband. En analys av en tänkt timmerram och takstol gjordes i ett beräkningsprogram för att på ett överslagsmässigt sätt bedöma vilka snittkrafter konstruktionen utsattes för. Ett laxförband i takstolen som visas i fig. 1 valdes ut för vidare analys. Manuell beräkning av bärförmågan i laxförbandet gjordes. Verifiering av beräkningarna gjordes därefter genom hållfasthetsprovning av förbandet i laborationslokal. Studien pekar mot att det går att med tillförlitlighet beräkna bärförmågan för ett traditionellt laxförband och att hänsyn skall tas till excentriciteter och varierande virkeskvalitet.
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Visualizing audit log events at the Swedish Police Authority to facilitate its use in the judicial system / Visualisering av spårbarhetslogg hos Polismyndigheten för att underlätta dess användning inom rättssystemetMichel, Hannes January 2019 (has links)
Within the Swedish Police Authority, physical users’ actions within all systems that manage sensitive information, are registered and sent to an audit log. The audit log contains log entries that consist of information regarding the events that occur by the performing user. This means that the audit log continuously manages massive amounts of data which is collected, processed and stored. For the police authority, the audit log may be useful for proving a digital trail of something that has occurred. An audit log is based upon the collected data from a security log. Security logs can collect datafrom most of the available systems and applications. It provides the availability for the organizationto implement network surveillance over the digital assets where logs are collected in real-time whichenables the possibility to detect any intrusion over the network. Furthermore, additional assets thatlog events are generated from are security software, firewalls, operating systems, workstations,networking equipment, and applications. The actors in a court of law usually don’t possess the technical knowledge required to interpret alog events since they can contain variable names, unparsed data or undefined values. Thisemphasizes the need for a user-friendly artifact of the audit log events that facilitates its use. Researching a way of displaying the current data format and displaying it in an improvedpresentable manner would be beneficial as an academic research by producing a generalizablemodel. In addition, it would prove useful for the internal investigations of the police authority sinceit was formed by their needs.
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Estudos e aplicações de barras de aço coladas, como conectores em lajes mistas de madeira e concreto para tabuleiros de pontes / Studies and applications of glued-in steel rods on shear connectors in mixed wood-concrete deck bridgesPigozzo, Julio César 06 December 2004 (has links)
As pontes tradicionais de madeira no Brasil, nem sempre atingem as condições plenamente satisfatórias em estradas vicinais, exigem manutenção contínua e a maioria não está adequada ao tráfego pesado usual. As pontes mistas de madeira e concreto destacam-se como alternativa econômica apresenta grande resistência e rigidez além de exigir baixa manutenção. Neste trabalho os estudos dos tabuleiros mistos de madeira e concreto para pontes desenvolveram-se em três fases: estudo da ancoragem de barras de aço coladas em peças estruturais de madeira; estudo dos conectores de cisalhamento formados por barras de aço coladas na madeira em corpos-de-prova mistos de madeira e concreto e, estudos; construções e análises de protótipos de tabuleiros mistos de madeira e concreto. Nos estudos de ancoragens, as barras de aço com superfície deformada, do tipo CA-50 com tensão de escoamento 'F IND.Y,K' = 500 MPa, foram coladas em furos com diâmetros maiores, inclinadas de '0, 45 e 90 GRAUS' em relação às fibras das madeiras. Utilizaram-se quatro tipos de resina epóxi e uma poliuretana, considerando as principais variáveis que influenciam na resistência de ancoragem. Os corpos-de-prova foram construídos com amostragens de madeiras de: Eucalyptus citriodora (ρ 12% = 1000 kg/'M POT.3') e Pinus oocarpa shiede (ρ 12% = 550 kg/'M POT.3'). Os testes de ancoragem apresentam as estimativas das resistências médias obtidas por meio de análise de regressão múltipla e as resistências características, obtidas pelo limite inferior do intervalo de confiança a 90%. Nos estudos dos conectores de cisalhamento utilizaram-se corpos-de-prova mistos, do tipo push out, executados com madeira roliça natural de Eucalyptus citriodora tratada com CCA e concreto armado de média resistência. Os conectores de cisalhamento, em três variações, foram executados com barras de aço do tipo CA-50 ancoradas na madeira, com a resina epóxi SIKADUR 32 fluido e inclinados de '45 GRAUS' em relação às fibras, os resultados apresentam, as resistências últimas médias, as resistências características; os valores médios e os valores característicos dos módulos de deslizamento da conexão. Nos estudos, projetos e execuções de dois tabuleiros mistos, de madeira e concreto, utilizaram-se toras de Eucalyptus citriodora tratadas com CCA, concreto armado de média resistência e conectores de barras de aço coladas com resina epóxi no formato X. Análises estáticas foram realizadas submetendo os tabuleiros às provas de carga, utilizando caminhões. Os deslocamentos na linha central transversal foram medidos e comparados com os valores teóricos calculados usando um modelo de cálculo que considera o tabuleiro misto como uma placa ortotrópica equivalente. Os conectores apresentaram alta resistência; alta rigidez e modo de ruptura uniforme. Os tabuleiros mistos de madeira e concreto apresentaram muito bom desempenho, confirmaram-se as hipóteses fundamentais e o modelo de cálculo proposto. / The traditional timber bridges in secondary roads in Brazil not always meet the requirements of quality, but they also demand continuing maintenance and adequacy to heavy traffic. The mixed wood-concrete deck bridges arise as a viable alternative, because of its low construction cost, low maintenance and its high strength and stiffness. In this thesis the mixed wood concrete deck bridge studies was showed in three phases: the experimental pull out strength results of bonded-in steel rods in wood beams studs; the experimental analysis on shear connectors in mixed wood concrete specimens using bonded-in steel bars and, designs; constructions and statistics tests on log-concrete composed deck bridges was presented too. In the anchorage studies the deformed and reinforced CA-50 steel bars, with the minimum yield strength of 500 Mpa, were bonded in holes drilled at angles of '0, 45 and 90 DEGREES' between the rods and on the direction of grain. Four types of epoxy and one polyurethane adhesive were used regarding the influence of the most significant variables. The specimens were made using Eucalyptus citriodora (ρ 12% = 1000 kg/'M POT.3') and Pinus oocarpa shiede (ρ 12% = 550 kg/'M POT.3') beams. The pull out tests presents the median strength results estimated by multiple regression analysis and the characteristics response estimated by the lower range in 90% of the confidence interval. In the shear connections studies were carried using specimens of push out tests type made of logs of Eucalyptus citriodora treated with CCA and medium strength reinforced concrete. The shear connectors, in three shapes, were made with CA-50 steel bars bonded-in wood with SIKADUR 32 fluid epoxi resin, with '45 DEGREES' angles between the rods and on the direction of grain. The results presents the ultimate limit strength median, the characteristics strength, the slip modulus medians and the characteristics slip modulus. In the studies, designs and executions of two mixed wood-concrete decks bridge were used made of logs of Eucalyptus citriodora treated with CCA, medium strength reinforced concrete, and bonded-in steel CA-50 rods, as shear connectors in X format. Same static loads test on the bridges was carried out using a truck. Deflections in the medium span transversal directions were measured and analytically predicted using an equivalent orthotropic plate model. The shear connectors showed high ultimate strength and stiffness and, uniforms failure mode. The results showed a very good performance to the composed log-concrete deck bridges, it confirms the fundamental hypothesis and calculus model suggested.
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Tend??ncias da ind??stria naval e as exporta????es de gran??is agr??colas no porto de Santos: detectando press??es para mudan??as organizacionaisNicoletti, Jose Roberto 08 February 2006 (has links)
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Previous issue date: 2006-02-08 / This research intends to get opinions, knowledge and expectations concerning to the professionals involved with export operations at specialized agribusiness port terminals, at Port of Santos - Brazil. Four main dimensions were studied: the characteristics of Dry Bulk Carrier Ships; the infrastructure of roads, railroads as well as the port; the expected influences brought by "ships of future" over export contracts; and the change needs forced by concurrential enviroment. The analysis is a part of agribusiness sector, specially the commodities soya beam and sugar. The understanding of port changes, market changes, as well as Naval Industry trends, can make the difference between those to be competitive or not, in a global market. To know in advance the answers for the needs of change, in what dimension to deal with and to act, become strategic factors to achieve the competitive advantage, comparing with other competitors port terminals. Many articles concerning the modernization and privatization of Port of Santos, can found in magazines and newspapers, but a few information have been published in books and scientific papers. The knowledge about the trends related to port enviroment, Naval Industry and maritime freight market were used to elaborate the questionnaire for the research, in order to investigate the opinion, the knowledge, and the professional's expectations. The findings, for the sample studied, indicates a good level of organizational changes. Therefore, the technological, regulatory, and market pressures over port terminals contributes to grow an isomorphism in organizational structures. This question could be investigated, on further studies. This theme is a wide-ranging in Management, as well as the field of Logistics. The present investigation brings more knowledge, and stimulates new scientific contributions in the field. / Este trabalho tem por objetivo pesquisar as opini??es, o conhecimento e as expectativas dos profissionais que participam das opera????es de exporta????o de gran??is agr??colas, por meio do Porto de Santos, sobre quatro dimens??es b??sicas: as caracter??sticas dos navios graneleiros; as infra-estruturas rodovi??ria, ferrovi??ria e portu??ria; o impacto do navio do futuro nos lotes vendidos e embarcados; e as necessidades de mudan??as provocadas pelo ambiente concorrencial. O setor analisado ?? o agro neg??cio, especialmente soja em gr??os e a????car. Entender as transforma????es portu??rias, do mercado, bem como os impactos que as tend??ncias da Ind??stria Naval trar??o aos terminais especializados, pode fazer a diferen??a entre ser competitivo globalmente, ou inviabilizar-se perante o mercado internacional. Conhecer previamente as necessidades de mudan??as, saber as respostas, e em que dimens??o agir, tornam-se fatores estrat??gicos para a vantagem competitiva, perante os terminais portu??rios concorrentes. Muito se fala a respeito do Porto de Santos, e de seu Programa de Arrendamentos e Parcerias, especialmente nos ??ltimos tr??s anos, em que o porto tem quebrado recordes anuais seguidos de movimenta????o de cargas. A maioria do material divulgado diz respeito a estat??sticas, artigos de revistas, de jornais de neg??cios, e de jornais de grande circula????o. Poucos livros e artigos cient??ficos tratam do tema. Por meio de pesquisa bibliogr??fica, procurou-se conhecer as mudan??as que t??m ocorrido, e as futuras tend??ncias, em tr??s principais esferas: o ambiente portu??rio, a Ind??stria Naval, e o mercado de fretes mar??timos. Essas informa????es serviram de base para a elabora????o do question??rio de pesquisa, com a finalidade de aferir a opini??o, o conhecimento, e as expectativas dos profissionais a respeito do assunto. Os resultados apontaram, para a amostra de sujeitos pesquisados, uma homogeneidade entre as opini??es, um bom grau de conhecimento sobre o tema, e uma boa sensibilidade sobre as necessidades de mudan??as organizacionais. As press??es tecnol??gicas, regulat??rias e comerciais, s??o fatores que contribuem para o direcionamento rumo ao isomorfismo das estruturas organizacionais dos terminais portu??rios analisados. Tal tema merece ser investigado em futuras pesquisas. O assunto desta pesquisa ?? abrangente, assim como o campo de conhecimento de Gest??o de Opera????es e Log??stica, e n??o se encerra com a realiza????o da presente pesquisa. Ela apenas amplia o conhecimento, instigando novas, e necess??rias, contribui????es acad??micas nesse campo.
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Extensions of the normal distribution using the odd log-logistic family: theory and applications / Extensões do normal distribuição utilizando a família odd log-logística: teoria e aplicaçõesBraga, Altemir da Silva 23 June 2017 (has links)
In this study we propose three new distributions and a study with longitudinal data. The first was the Odd log-logistic normal distribution: theory and applications in analysis of experiments, the second was Odd log-logistic t Student: theory and applications, the third was the Odd log-logistic skew normal: the new distribution skew-bimodal with applications in analysis of experiments and the fourth regression model with random effect of the Odd log-logistic skew normal distribution: an application in longitudinal data. Some have been demonstrated such as symmetry, quantile function, some expansions, ordinary incomplete moments, mean deviation and the moment generating function. The estimation of the model parameters were approached by the method of maximum likelihood. In applications were used regression models to data from a completely randomized design (CRD) or designs completely randomized in blocks (DBC). Thus, the models can be used in practical situations for as a completely randomized designs or completely randomized blocks designs, mainly, with evidence of asymmetry, kurtosis and bimodality. / A distribuição normal é uma das mais importantes na área de estatística. Porém, não é adequada para ajustar dados que apresentam características de assimetria ou de bimodalidade, uma vez que tal distribuição possui apenas os dois primeiros momentos, diferentes de zero, ou seja, a média e o desvio-padrão. Por isso, muitos estudos são realizados com a finalidade de criar novas famílias de distribuições que possam modelar ou a assimetria ou a curtose ou a bimodalidade dos dados. Neste sentido, é importante que estas novas distribuições tenham boas propriedades matemáticas e, também, a distribuição normal como um submodelo. Porém, ainda, são poucas as classes de distribuições que incluem a distribuição normal como um modelo encaixado. Dentre essas propostas destacam-se: a skew-normal, a beta-normal, a Kumarassuamy-normal e a gama-normal. Em 2013 foi proposta a nova família X de distribuições Odd log-logística-G com o objetivo de criar novas distribuições de probabildade. Assim, utilizando as distribuições normal e a skew-normal como função base foram propostas três novas distribuições e um quarto estudo com dados longitudinais. A primeira, foi a distribuição Odd log-logística normal: teoria e aplicações em dados de ensaios experimentais; a segunda foi a distribuição Odd log-logística t Student: teoria e aplicações; a terceira foi a distribuição Odd log-logística skew-bimodal com aplicações em dados de ensaios experimentais e o quarto estudo foi o modelo de regressão com efeito aleatório para a distribuição distribuição Odd log-logística skew-bimodal: uma aplicação em dados longitudinais. Estas distribuições apresentam boas propriedades tais como: assimetria, curtose e bimodalidade. Algumas delas foram demonstradas como: simetria, função quantílica, algumas expansões, os momentos incompletos ordinários, desvios médios e a função geradora de momentos. A flexibilidade das novas distrições foram comparada com os modelos: skew-normal, beta-normal, Kumarassuamy-normal e gama-normal. A estimativas dos parâmetros dos modelos foram obtidas pelo método da máxima verossimilhança. Nas aplicações foram utilizados modelos de regressão para dados provenientes de delineamentos inteiramente casualizados (DIC) ou delineamentos casualizados em blocos (DBC). Além disso, para os novos modelos, foram realizados estudos de simulação para verificar as propriedades assintóticas das estimativas de parâmetros. Para verificar a presença de valores extremos e a qualidade dos ajustes foram propostos os resíduos quantílicos e a análise de sensibilidade. Portanto, os novos modelos estão fundamentados em propriedades matemáticas, estudos de simulação computacional e com aplicações para dados de delineamentos experimentais. Podem ser utilizados em ensaios inteiramente casualizados ou em blocos casualizados, principalmente, com dados que apresentem evidências de assimetria, curtose e bimodalidade.
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