This thesis deals with the problem of displaying graphical outputs so that a certain fact is hidden. The aim of this thesis is to provide basic information about graphical outputs. Subsequently, outline the issue of their possible use or misuse and provide basic advice on what to focus on graphical outputs in order not to deceive the graph reader. This thesis is divided into two parts - the theoretical part and the practical part. The theoretical part contains a literary overview of the problems of graphical outputs and their processing. The practical part describes the research on practical graphs carried out on the focus group and individual respondents. Subsequently, the practical part includes the evaluation of this research and the drawing of basic recommendations for reading the graphs.

A constante evolução da tecnologia em saúde permite diagnósticos clínicos cada vez mais rápidos e precisos, porém eles não são isentos de danos. Conhecer e calcular a capacidade preditiva de classificadores de risco é um passo fundamental no desenvolvimento de políticas de saúde e na criação de protocolos clínicos. O processo de avaliação de um teste diagnóstico normalmente tem início com o preenchimento da tabela de contingência. Testes diagnósticos com elevado número de falso positivos geram ansiedade, exames adicionais e tratamentos desnecessários. Testes diagnósticos com elevado número de falso negativos podem contribuir para demoras desnecessárias no tratamento de uma possível doença, podendo dificultar sua cura. A partir da experiência adquirida com a análise da capacidade preditiva do partograma da OMS, esta tese apresenta o desenvolvimento de um novo indicador de capacidade preditiva e diagnóstica de testes. Justifica-se este novo desenvolvimento pela necessidade de simplificar, integralizar e exibir de forma conjunta os principais parâmetros necessários à avaliação da capacidade preditiva e diagnóstica de testes. A avalição dos partogramas de 9.995 mulheres da Nigéria e Uganda mostrou que a linha de alerta deste instrumento possui uma baixa capacidade diagnóstica como preditor para desfechos adversos graves no trabalho de parto. A partir desses e outros resultados, em fevereiro de 2018 a OMS recomendou mudanças no partograma. Com isso, foi explorado o uso do gráfico-radar como uma ferramenta para facilitar a comunicação dos parâmetros já existentes utilizados na avaliação da capacidade diagnóstica dos testes. Sete documentos com diretrizes em saúde materna publicados pela OMS entre os anos de 2016 a 2018 foram utilizados nesse processo. Utilizando o cálculo da área inscrita do gráfico-radar apresenta-se também um novo indicador integrativo para avaliação da capacidade preditiva de testes diagnósticos, o Índice de Máxima Acurácia (IMA) / The constant evolution of health technology allows for faster and more accurate clinical diagnoses, but they are not harmless. Knowing and calculating the predictive capacity of risk classifiers is a fundamental step in the development of health policies and in the creation of clinical protocols. The process of evaluating a diagnostic test usually begins with the completion of the contingency table. Diagnostic tests with high false positives generate avoidable distress, additional tests and unnecessary treatments. Diagnostic tests with high false negatives may contribute to unnecessary delays in the treatment of a possible disease. Based on the experience gained with the analysis of predictive capacity of the WHO partograph, this thesis presents the development of a new indicator of predictive and diagnostic capacity of tests. This new development is justified by the need to simplify, integrate and display together the main parameters necessary for the evaluation of the predictive and diagnostic capacity of tests. The assessment of the partographs of 9,995 women from Nigeria and Uganda showed that the alert line of this instrument has a low diagnostic capacity as a predictor for serious adverse outcomes in labor. From these and other results, in February 2018 the WHO recommended changes in the partograph. The use of the radar chart was explored as a tool to facilitate the communication of the existing parameters used in the evaluation of the diagnostic capacity of the tests. Seven documents with guidelines on maternal health published by WHO between 2016 and 2018 were used in this process. Using the calculated area of the radar chart, a new integrative indicator for the predictive capacity of diagnostic tests, the Index of Maximum Accuracy (IMA), is also presented

O objetivo principal deste trabalho é demonstrar a especificidade do universo insular. Para tal, os conceitos de insularidade, maritimidade, litoralismo, ilheidade e condição arquipelágica foram elencados de modo a abarcar fatores comuns no âmbito da miríade de possibilidades que as ilhas são capazes de ensejar. O intento central foi, assim, explorar esses conceitos por intermédio de representações gráficas capazes de transcender a simples analogia com a realidade, típica dos mapas. Trata-se, pois, do método da Coremática, desenvolvido pelo geógrafo francês Roger Brunet na busca de uma argumentação feita não somente pelas palavras, mas pelas imagens. A princípio, com as possibilidades de representação geométrica existentes, é possível compor uma série de figuras estruturantes ou basilares que, combinada ou individualmente, são capazes de expressar as dinâmicas fundamentais de determinado espaço geográfico. Com efeito, lançou-se mão do método coremático para demonstrar a especificidade da forma insular, tendo, como estudo de caso, Montão de Trigo, uma ilha localizada no litoral norte do estado de São Paulo. Empregou-se, assim, uma modelização gráfica da ilha, a partir da qual se foi capaz de identificar determinados traços distintivos, tais quais a relação terra-mar; as ligações internas e externas; as centralidades intrainsulares; as formas de compartimentar o território; o direito de propriedade e o direito de uso do espaço insular; os graus de antropização; e, finalmente, o papel da influência marítima no assentamento humano. / This work shows the specific feature of the islands. To do so, we used the concepts of insularity, maritime dimension, coastal condition, sense of belonging to an island and archipelagic nature, that can describe different situations related to the islands. The main idea was to present these concepts by using some graphical depictions, which can go beyond the simple analogy with geographical reality that the maps usually present; by using, therefore, a method that could argue with images instead of words: the Chorématique, developed by the French geographer Roger Brunet. Firstly, with the current representation possibilities in terms of geometry, Brunet proposed some basic or structural images that can be used (separately or jointly) in different situations to show the most important aspects of a region. By applying this method to demonstrate the island distinctiveness, we created some basic images as well as Brunet done. Then, we presented a graphic model that shows the essential geography of Montão de Trigo, a small island in the northern coast of São Paulo State, Brazil. Among all the features of the island, there are different types of phenomena: relationships between ocean and land; domestic and foreign linkages; center places; natural and human regions; ownership and rights of use the land; degrees of human intervention; and, finally, the maritime influences in the process of human settlement.

O século XX marca um período de intensas mudanças nos métodos e nas práticas científicas, face aos novos desafios vividos pela sociedade contemporânea, como a industrialização, crescimento demográfico, expansão urbana e a perda da biodiversidade. Esta nova tendência do cenário mundial faz com que a compreensão do espaço deixe de ser meramente descritiva e independente da participação da sociedade. No âmbito da Geografia, um dos caminhos adotados para tratar estas questões é o conceito de Paisagem fundamentado na teoria dos Geossistemas como orientação viável para o desenvolvimento de pesquisas fundamentais (acadêmicas) e experimentais (aplicadas). No Brasil, uma área que chama atenção pela intensa concentração populacional e a quase extinção da cobertura vegetal é a região do Vale do Rio Paraíba do Sul, face seu histórico de ocupação que, ao longo do tempo, lhe atribuiu um papel singular no cenário econômico nacional. Diante destas premissas, o objetivo da pesquisa foi identificar e caracterizar as unidades ambientais da Bacia do Rio Buquira no Estado de São Paulo, relacionando os aspectos da sociedade e da natureza mediante a elaboração de mapas analíticos que desembocaram num mapa de síntese, como uma etapa no processo do conhecimento. / The XXth Century marks a period of intense change in the methods and scientific practices, meet the new challenges faced by contemporary society, such as industrialization, demographic increasing, urban expansion and loss of biodiversity. In this new trend of world scenario makes understanding of space is no longer seen only in a descriptive way and independent of participation of society. In the scope of Science one theme may allow a reflection about Environmental from the analysis of social organizations allied to a healthy environment is the Geography has the use of landscape concept on the theory of Geossistemas as viable guide for the development of fundamental research (academic) and experimental (applied). In Brazil, an area need care when you think the environmental problems is the Paraiba do Sul River Basin because its history of occupation, which has experienced several economic cycles that gives a major economic role in the national scene in the opposite way, presents a compromising environmental quality. Due to these reasons this work has objective the identification and characterization of environmental units of Buquira`s River Basin in the State of São Paulo, related the social and natural aspects to the space through the development of analytic maps that ran into a synthesis maps one as a step in the knowledge process.

<div> <div> <div> <p>Currently there is a need for research that explores students’ understanding of advanced topics in order to improve teaching and learning beyond the context of introductory-level courses. This work investigates students’ reasoning about graphs used in enzyme kinetics. Using semi-structured interviews and a think aloud-protocol, 14 second-year students enrolled in a biochemistry course were provided two graphs to prompt their reasoning, a typical Michaelis-Menten graph and a Michaelis-Menten graph involving enzyme inhibition. Student responses were coded using a combination of inductive and deductive analysis, influenced by the resource-based model of cognition. Results involve a discussion regarding how students utilized mathematical resources to reason about chemical kinetics and enzyme kinetics, such as engaging in the use of symbolic/graphical forms and focusing on surface-level features of the equations/graphs. This work also addresses student conceptions of the particulate-level mechanism associated with competitive, noncompetitive, and uncompetitive enzyme inhibition. Based on the findings of this study, suggestions are made regarding the teaching and learning of enzyme kinetics. </p> </div> </div> </div>

O objeto de estudo desta tese é o conjunto de fatores que determina uma condição para a vitalidade dos espaços na arquitetura, em particular, nos edifícios inseridos no meio urbano. Para caracterização e registro desta condição, empreendeu-se um conjunto de leituras espaciais tendo como objeto oito obras emblemáticas pertencentes à cultura arquitetônica internacional. Os elementos conceituais que deram suporte às leituras, chamados de \'vias\', foram formulados tendo como base um referencial teórico que trata da análise do espaço na arquitetura e de seus recursos gráficos. A hipótese subjacente é a de que a leitura da arquitetura por meio do exame de suas representações gráficas, quando conduzida com base metodológica, tem a capacidade de revelar aspectos essenciais de sua condição espacial. O objetivo foi compreender a relação entre os conceitos pensados para os espaços na arquitetura e as formas espaciais decorrentes destes. O estudo indicou que a estrutura temática sugerida e os recursos gráficos que dela derivaram não apenas revelaram-se ferramentas de auxílio importantes às leituras mas também se mostraram fundamentais para muitas demonstrações empreendidas concernentes à condição espacial arquitetônica. / The object of this thesis is the set of factors that determines a condition for the vitality of the spaces in architecture, in particular in buildings inserted into the urban environment. To characterize and record this condition, undertook a set of spatial readings on eight emblematic works of the international architectural culture. The conceptual elements that supported the readings, called \"ways\", were formulated based on a theoretical framework that deals with the analysis of space in architecture and its graphics. The underlying assumption is that the architecture reading by examining their graphical representations, when conducted on a methodological basis, has the ability to reveal key aspects of spatial condition. The objective was to understand the relationship between the concepts on the spaces in architecture and their resulting spatial forms. The study indicated that the thematic structure suggested and its graphics features not only proved to be important tools to aid readings but were also critical to many demonstrations undertaken concerning the architectural space condition.

O objeto de estudo desta tese é o conjunto de fatores que determina uma condição para a vitalidade dos espaços na arquitetura, em particular, nos edifícios inseridos no meio urbano. Para caracterização e registro desta condição, empreendeu-se um conjunto de leituras espaciais tendo como objeto oito obras emblemáticas pertencentes à cultura arquitetônica internacional. Os elementos conceituais que deram suporte às leituras, chamados de \'vias\', foram formulados tendo como base um referencial teórico que trata da análise do espaço na arquitetura e de seus recursos gráficos. A hipótese subjacente é a de que a leitura da arquitetura por meio do exame de suas representações gráficas, quando conduzida com base metodológica, tem a capacidade de revelar aspectos essenciais de sua condição espacial. O objetivo foi compreender a relação entre os conceitos pensados para os espaços na arquitetura e as formas espaciais decorrentes destes. O estudo indicou que a estrutura temática sugerida e os recursos gráficos que dela derivaram não apenas revelaram-se ferramentas de auxílio importantes às leituras mas também se mostraram fundamentais para muitas demonstrações empreendidas concernentes à condição espacial arquitetônica. / The object of this thesis is the set of factors that determines a condition for the vitality of the spaces in architecture, in particular in buildings inserted into the urban environment. To characterize and record this condition, undertook a set of spatial readings on eight emblematic works of the international architectural culture. The conceptual elements that supported the readings, called \"ways\", were formulated based on a theoretical framework that deals with the analysis of space in architecture and its graphics. The underlying assumption is that the architecture reading by examining their graphical representations, when conducted on a methodological basis, has the ability to reveal key aspects of spatial condition. The objective was to understand the relationship between the concepts on the spaces in architecture and their resulting spatial forms. The study indicated that the thematic structure suggested and its graphics features not only proved to be important tools to aid readings but were also critical to many demonstrations undertaken concerning the architectural space condition.

En dépit de leur omniprésence et de leur rôle essentiel dans nos vies professionnelles et personnelles, les représentations graphiques, qu'elles soient numériques ou sur papier, ne sont pas accessibles aux personnes déficientes visuelles car elles ne fournissent pas d'informations tactiles. Par ailleurs, les inégalités d'accès à ces représentations ne cessent de s'accroître ; grâce au développement de représentations graphiques dynamiques et disponibles en ligne, les personnes voyantes peuvent non seulement accéder à de grandes quantités de données, mais aussi interagir avec ces données par le biais de fonctionnalités avancées (changement d'échelle, sélection des données à afficher, etc.). En revanche, pour les personnes déficientes visuelles, les techniques actuellement utilisées pour rendre accessibles les cartes et les diagrammes nécessitent l'intervention de spécialistes et ne permettent pas la création de représentations interactives. Cependant, les récentes avancées dans le domaine de l'adaptation automatique de contenus laissent entrevoir, dans les prochaines années, une augmentation de la quantité de contenus adaptés. Cette augmentation doit aller de pair avec le développement de dispositifs utilisables et abordables en mesure de supporter l'affichage de représentations interactives et rapidement modifiables, tout en étant accessibles aux personnes déficientes visuelles. Certains prototypes de recherche s'appuient sur une représentation numérique seulement : ils peuvent être instantanément modifiés mais ne fournissent que très peu de retour tactile, ce qui rend leur exploration complexe d'un point de vue cognitif et impose de fortes contraintes sur le contenu. D'autres prototypes s'appuient sur une représentation numérique et physique : bien qu'ils puissent être explorés tactilement, ce qui est un réel avantage, ils nécessitent un support tactile qui empêche toute modification rapide. Quant aux dispositifs similaires à des tablettes Braille, mais avec des milliers de picots, leur coût est prohibitif. L'objectif de cette thèse est de pallier les limitations de ces approches en étudiant comment développer des cartes et diagrammes interactifs physiques, modifiables et abordables. Pour cela, nous nous appuyons sur un type d'interface qui a rarement été étudié pour des utilisateurs déficients visuels : les interfaces tangibles, et plus particulièrement les interfaces tangibles sur table. Dans ces interfaces, des objets physiques représentent des informations numériques et peuvent être manipulés par l'utilisateur pour interagir avec le système, ou par le système lui-même pour refléter un changement du modèle numérique - on parle alors d'interfaces tangibles sur tables animées, ou actuated. Grâce à la conception, au développement et à l'évaluation de trois interfaces tangibles sur table (les Tangible Reels, la Tangible Box et BotMap), nous proposons un ensemble de solutions techniques répondant aux spécificités des interfaces tangibles pour des personnes déficientes visuelles, ainsi que de nouvelles techniques d'interaction non-visuelles, notamment pour la reconstruction d'une carte ou d'un diagramme et l'exploration de cartes de type " Pan & Zoom ". D'un point de vue théorique, nous proposons aussi une nouvelle classification pour les dispositifs interactifs accessibles. / Despite their omnipresence and essential role in our everyday lives, online and printed graphical representations are inaccessible to visually impaired people because they cannot be explored using the sense of touch. The gap between sighted and visually impaired people's access to graphical representations is constantly growing due to the increasing development and availability of online and dynamic representations that not only give sighted people the opportunity to access large amounts of data, but also to interact with them using advanced functionalities such as panning, zooming and filtering. In contrast, the techniques currently used to make maps and diagrams accessible to visually impaired people require the intervention of tactile graphics specialists and result in non-interactive tactile representations. However, based on recent advances in the automatic production of content, we can expect in the coming years a growth in the availability of adapted content, which must go hand-in-hand with the development of affordable and usable devices. In particular, these devices should make full use of visually impaired users' perceptual capacities and support the display of interactive and updatable representations. A number of research prototypes have already been developed. Some rely on digital representation only, and although they have the great advantage of being instantly updatable, they provide very limited tactile feedback, which makes their exploration cognitively demanding and imposes heavy restrictions on content. On the other hand, most prototypes that rely on digital and physical representations allow for a two-handed exploration that is both natural and efficient at retrieving and encoding spatial information, but they are physically limited by the use of a tactile overlay, making them impossible to update. Other alternatives are either extremely expensive (e.g. braille tablets) or offer a slow and limited way to update the representation (e.g. maps that are 3D-printed based on users' inputs). In this thesis, we propose to bridge the gap between these two approaches by investigating how to develop physical interactive maps and diagrams that support two-handed exploration, while at the same time being updatable and affordable. To do so, we build on previous research on Tangible User Interfaces (TUI) and particularly on (actuated) tabletop TUIs, two fields of research that have surprisingly received very little interest concerning visually impaired users. Based on the design, implementation and evaluation of three tabletop TUIs (the Tangible Reels, the Tangible Box and BotMap), we propose innovative non-visual interaction techniques and technical solutions that will hopefully serve as a basis for the design of future TUIs for visually impaired users, and encourage their development and use. We investigate how tangible maps and diagrams can support various tasks, ranging from the (re)construction of diagrams to the exploration of maps by panning and zooming. From a theoretical perspective we contribute to the research on accessible graphical representations by highlighting how research on maps can feed research on diagrams and vice-versa. We also propose a classification and comparison of existing prototypes to deliver a structured overview of current research.

Este trabalho é resultado de uma tese de doutorado realizada na Universidade de São Paulo, com o objetivo de: Analisar a forma de representação cartográfica temática presente nos mapas turísticos destinados aos visitantes no Município de Ponta Grossa PR. Tal intuito veio de encontro à problemática observada nos diferentes usos simbólicos em mapas ofertados aos turistas, em diferentes localidades do Estado do Paraná e até mesmo do País, criando uma imagem local muitas vezes não correspondente à realidade identitária cultural destes respectivos espaços. No caso do Município de Ponta Grossa PR (recorte espacial escolhido para estudo), os mapas turísticos focalizam com grande ênfase o Parque Estadual de Vila Velha, deixando pouco retratados, ou de difícil localização, outros pontos turísticos importantes como: Buraco do Padre, Cachoeira da Mariquinha, Rio Verde, Capão da Onça, Parque Margharita Mazzine, Vila Hilda, Estação Saudade e tantos mais. Isto permite de certa forma condenar o município a uma espécie de extensão da capital estadual (Curitiba), dentro dos roteiros turísticos, penalizando fortemente este setor econômico, e, maculando de insignificantes outras potencialidades naturais e culturais locais. Assim, apesar de um número expressivo de visitantes que vem até o município, estes turistas praticamente só comparecem até o Parque e já retornam, sem visitar demais áreas e sem sequer conhecer a cidade. O resultado desse descaso é o desinteresse de maiores políticas públicas que fomentem uma ampliação nas infraestruturas de acesso, de atendimento, de acomodação e até mesmo de dinamização frente ao que poderia ser um salto para o turismo sustentável local. No desenvolvimento da pesquisa, utilizamos como metodologia de trabalho a análise de materiais cartográficos (mapas turísticos) e as entrevistas com usuários do serviço (turistas e visitantes locais), diagnosticando a eficácia da representação simbólica empregada nos dois mapas mais atualizados, correlacionando isto às causas e consequências do resultado de tal material produzido, como instrumento de marketing, de localização e informação. Também foram entrevistados os sujeitos responsáveis pela produção do material de divulgação aos visitantes, para saber sua formação profissional e critérios considerados importantes na elaboração dos mapas, bem como os chefes de departamento de turismo, para permitir um entendimento, frente ao ponto de vista dos mesmos, quanto ao tipo de material ofertado, fazendo uma correlação com os dados quantitativos obtidos no campo de investigação anterior. Nossos estudos se basearam com prioridade às concepções teóricas atuais e internacionais de Mark Monmonier, (How to lie with maps), para discutir as mentiras presentes nos mapas, e em Jacques Bertin, (Sémiologie Graphique), de modo a retratar as formas convencionais de comunicação cartográfica. A conclusão final da pesquisa aponta para uma gama de artifícios pictóricos com o intuito de estimular o imaginário dos visitantes e vender-lhes tal fantasia em detrimento de emprego de variáveis visuais convencionais à cartografia. O que justifica esta ocorrência é o interesse de mercado de órgãos específicos, e a responsabilidade profissional de produção de mapas que é muitas vezes atribuída a sujeitos não qualificados para este exercício. É necessário nos preocuparmos com o rigor de produções científicas, como o instrumental cartográfico, visto que é visível a banalização que, muitas vezes, é atribuída a esta área do conhecimento, diante da facilidade de reprodução de imagens, via avanço tecnológico. / This work is the result of a doctoral thesis held at the University of São Paulo, with the objective: \"Examining thematic cartographic representation present in tourist maps for visitors in the municipality of Ponta Grossa-PR\". This order came the problems observed in different uses symbolic maps offered to tourists, in different localities of the State of Paraná and even the country, creating a local image often not corresponding to the reality of cultural identity of these spaces. In the case of the municipality of Ponta Grossa PR (Snip space chosen for study), tour focused on maps with great emphasis the Vila Velha State Park, leaving little depicted, or difficult location, other important sights: Hole of Priest, Mariquinha Waterfall, Green River Resort, Capão of ounce, Margharita Mazzine Park, Hilda Village, Saudade Station and many more. This allows somewhat condemn the municipality to a kind of extension of the State capital (Curitiba) within the itineraries pollute heavily this economic sector, and maculando of insignificant other potential natural and cultural sites. Thus, despite an overwhelming number of visitors who come to the city, these tourists virtually only comes to the Park and return, without visiting other areas and without even knowing the city. The rest is the lack of major public policies that promote a magnification in infrastructure access service, accommodation and even pivoting forward that could be a leap into the local sustainable tourism. In the development of search we use as working methodology of cartographic materials analysis (tourist maps) and interviews with users of the service (tourists and visitors locations), diagnosing the effectiveness of symbolic representation used in the two most up-to-date maps, correlating it to the causes and consequences of the outcome of such material produced as marketing tool, location and information. Also interviewed every responsible production of material to visitors, to learn their vocational training and criteria are considered important in the preparation of maps, as well as the heads of Department of tourism, to allow an understanding to the point of view, on the type of material contributed by doing a correlation with the quantitative data from previous research. Our studies are based, with priority to current theoretical conceptions and international Monmonier, Mark (how to lie with maps) to discuss the \"lies\" present on maps, and Jacques Bertin, (Sémiologie Graphique) to portray the conventional forms of cartographic communication. The final completion of the survey points to a range of pictorial artifice to stimulate the imagination of visitors and sell them this fantasy to the detriment of employment of conventional Visual variables to cartography. What justifies this occurrence is the interest of specific organs market and professional liability for the production of maps is often assigned to non-qualified for this exercise. You need to concern ourselves with the rigor of scientific productions such as instrumental cartographic, since it is visible to the banal, which is often assigned to this area of knowledge, given the ease of reproduction of images, via technological advance.

This thesis provides novel methodology for statistical analysis of paired high-dimensional genomic data, with the aimto identify gene interactions specific to each group of samples as well as the gene connections that change between the two classes of observations. An example of such groups can be patients under two medical conditions, in which the estimation of gene interaction networks is relevant to biologists as part of discerning gene regulatory mechanisms that control a disease process like, for instance, cancer. We construct these interaction networks fromdata by considering the non-zero structure of correlationmatrices, which measure linear dependence between random variables, and their inversematrices, which are commonly known as precision matrices and determine linear conditional dependence instead. In this regard, we study three statistical problems related to the testing, single estimation and joint estimation of (conditional) dependence structures. Firstly, we develop hypothesis testingmethods to assess the equality of two correlation matrices, and also two correlation sub-matrices, corresponding to two classes of samples, and hence the equality of the underlying gene interaction networks. We consider statistics based on the average of squares, maximum and sum of exceedances of sample correlations, which are suitable for both independent and paired observations. We derive the limiting distributions for the test statistics where possible and, for practical needs, we present a permuted samples based approach to find their corresponding non-parametric distributions. Cases where such hypothesis testing presents enough evidence against the null hypothesis of equality of two correlation matrices give rise to the problem of estimating two correlation (or precision) matrices. However, before that we address the statistical problem of estimating conditional dependence between random variables in a single class of samples when data are high-dimensional, which is the second topic of the thesis. We study the graphical lasso method which employs an L1 penalized likelihood expression to estimate the precision matrix and its underlying non-zero graph structure. The lasso penalization termis given by the L1 normof the precisionmatrix elements scaled by a regularization parameter, which determines the trade-off between sparsity of the graph and fit to the data, and its selection is our main focus of investigation. We propose several procedures to select the regularization parameter in the graphical lasso optimization problem that rely on network characteristics such as clustering or connectivity of the graph. Thirdly, we address the more general problem of estimating two precision matrices that are expected to be similar, when datasets are dependent, focusing on the particular case of paired observations. We propose a new method to estimate these precision matrices simultaneously, a weighted fused graphical lasso estimator. The analogous joint estimation method concerning two regression coefficient matrices, which we call weighted fused regression lasso, is also developed in this thesis under the same paired and high-dimensional setting. The two joint estimators maximize penalized marginal log likelihood functions, which encourage both sparsity and similarity in the estimated matrices, and that are solved using an alternating direction method of multipliers (ADMM) algorithm. Sparsity and similarity of thematrices are determined by two tuning parameters and we propose to choose them by controlling the corresponding average error rates related to the expected number of false positive edges in the estimated conditional dependence networks. These testing and estimation methods are implemented within the R package ldstatsHD, and are applied to a comprehensive range of simulated data sets as well as to high-dimensional real case studies of genomic data. We employ testing approaches with the purpose of discovering pathway lists of genes that present significantly different correlation matrices on healthy and unhealthy (e.g., tumor) samples. Besides, we use hypothesis testing problems on correlation sub-matrices to reduce the number of genes for estimation. The proposed joint estimation methods are then considered to find gene interactions that are common between medical conditions as well as interactions that vary in the presence of unhealthy tissues.