We explore visualization and abstraction approaches to represent neuronal data. Neuroscientists acquire electron microscopy volumes to reconstruct a complete wiring diagram of the neurons in the brain, called the connectome. This will be crucial to understanding brains and their development. However, the resulting data is complex and large, posing a big challenge to existing visualization techniques in terms of clarity and scalability. We describe solutions to tackle the problems of scalability and cluttered presentation. We first show how a query-guided interactive approach to visual exploration can reduce the clutter and help neuroscientists explore their data dynamically. We use a knowledge-based query algebra that facilitates the interactive creation of queries. This allows neuroscientists to pose domain-specific questions related to their research. Simple queries can be combined to form complex queries to answer more sophisticated questions. We then show how visual abstractions from 3D to 2D can significantly reduce the visual clutter and add clarity to the visualization so that scientists can focus more on the analysis. We abstract the topology of 3D neurons into a multi-scale, relative distance-preserving subway map visualization that allows scientists to interactively explore the morphological and connectivity features of neuronal cells. We then focus on the process of acquisition, where neuroscientists segment electron microscopy images to reconstruct neurons. The segmentation process of such data is tedious, time-intensive, and usually performed using a diverse set of tools. We present a novel web-based visualization system for tracking the state, progress, and evolution of segmentation data in neuroscience. Our multi-user system seamlessly integrates a diverse set of tools. Our system provides support for the management, provenance, accountability, and auditing of large-scale segmentations. Finally, we present a novel architecture to render very large volumes interactively. We focus on two aspects: (1) Segmented objects are often toggled on and off by an interactive query, which makes it unfeasible to pre-compute a well-adapted space subdivision. (2) To scale to large data, culling and empty-space skipping must scale with the output size instead of the input volume. Our approach combines the advantages of object- and image-order stages of the empty-space skipping process.

Society generates more and more data every day, and with competent ways to visualize it, we can learn new things about the world we live in. While traditional visualizations try to stay clear of 3D graphs because they are hard for a user to process without proper depth cues, VR technology allows us to better perceive 3D structures, but what happens to our overview of the data when we perceive and interact with it in 3D? 6 participants were subject to a 3D VR visualization of customer data with filtering possibilities, where they were to perform a series of short tasks as well as a more open-ended free form task. Qualitative data was gathered through extensive semi-structured interviews. Quantitative supportive data was gathered as well in the form of interaction logs, time to complete tasks and the Presence Questionnaire. After this first round of tests, feedback and data was compiled into a new version of the visualization that was then tested on seven new participants. Results showed that seeing the graph from different perspectives was important to gaining an overview of the 3D graph, but also to actively interact with the data helped participants gain an overview by digging deeper into the data. In order to dig into the data in the 3D graph, participants expressed that they would’ve liked to be able to compare subsets of the data. / Vi genererar ofantliga mängder data varje dag, men utan att visualisera denna data är det inte säkert att vi lär oss någonting av den. Med detta följer även ett behov av att visualisera denna data i flera dimensioner, något som varit svårt i informationsvisualiseringar tidigare då det är svårt att representera djup på en platt skärm så att människor förstår. Med VR-teknik kan vi däremot använda detta djupseende i informationsvisualiseringar, men vad händer med vår överblick av informationen när vi ser och interagerar med den i 3D?   6 testpersoner fick interagera med en 3D-visualisering av kunddata med filtreringsmöjligheter i VR och fick i denna utföra en serie mindre uppgifter samt en större, fri uppgift. Under testet samlades kvalitativ data in i form av utförliga semi-strukturerade intervjuer och kvantitativ supportdata i form av loggar av interaktioner, tid att slutföra uppgifter samt svar från Presence Questionnaire för alla testpersoner. Åsikterna från denna testrunda användes sedan för att skapa en ny version av 3Dvisualiseringen som sedan testades på 7 nya personer enligt samma studieformat.   Resultaten visade att det var viktigt att kunna se grafen från olika perspektiv för att få en överblick, såväl som att kunna aktivt filtrera och interagera med visualiseringen för att kunna gräva djupare i datan. För att kunna gräva djupare kände många testpersoner att de behövde ett sätt att enkelt kunna jämföra delmängder av datan med varandra.

As we are heading into immersive virtual reality environments for different purposes - entertainment being the most prominent lately - we should consider how we design interactive information visualizations for VR. Is it wise to hold onto the same elements of interaction with which we are familiar from contemporary web-based interfaces? The study explores this question along with others, to explore ways to conduct familiar filtering operations known from web environments, in VR. An interactive information visualization application in VR was created to evaluate two web-inspired interaction methods used for filtering data. Thirteen users participated in the tests, in which each participant worked through eight predetermined tasks as well as one open-ended task. Qualitative feedback was gathered both through think-alouds during the tasks and in semi-structured interviews when the test had been concluded. Quantitative data was gathered in the application, containing logs of usage statistics. Results show that using web-inspired interaction methods to carry out filtering operations in VR helped the participants to understand the functionality of the interactions. By implementing haptic and visual feedback, natural interactions can be imitated which according to the results of the study generally is perceived as helpful while making the interactions feel more natural. Designing the interaction methods to function like previously known interactions (such as ones found in web interfaces) helped the participants to understand the functionality of the filters. / I och med framfarten av VR och dess olika användningsområden – där underhållning gått i bräschen på senare tid – borde vi fundera på hur vi designar interaktiva informationsvisualiseringar för VR. Är det klokt att hålla fast vid samma interaktionselement som vi känner igen från webbaserade gränssnitt? Studien utforskar denna fråga tillsammans med andra, för att utforska sätt att genomföra bekanta filtreringsoperationer som känns igen från webbmiljöer, i VR.   En interaktiv informationsvisualiseringsapplikation i VR skapades för att utvärdera två webbinspirerade interaktionsmetoder som användes för att filtrera data. Tretton användare deltog i studien, där varje deltagare tog sig igenom åtta förbestämda uppgifter samt en öppen uppgift. Kvalitativ återkoppling samlades in både via think-alouds under uppgifterna samt i semistrukturerade intervjuer när testet hade avslutats. Kvantitativa data samlades in i applikationen och innehöll användningsstatistik.   Resultaten visar att användandet av webbinspirerade interaktionsmetoder för att genomföra filtreringsoperationer i VR hjälpte deltagarna att förstå interaktionens funktionalitet. Genom att implementera haptisk och visuell feedback kan naturliga interaktioner efterliknas, vilket enligt studiens resultat uppfattas som hjälpsamt samtidigt som interaktionerna kändes mer naturliga. Att utforma interaktionsmetoderna för att efterlikna de som återfinns i webbgränssnitt hjälpte deltagarna att förstå filtrens funktionalitet.

Ergonomie ist seit Jahren ein wichtiges Thema in allen Bereichen des Lebens. Unter anderem beinhaltet dies auch die Anpassung der Arbeit an den Arbeiter, um so kurz- und langfristige gesundheitliche Probleme zu minimieren. Ergonomen begutachten in diesem Kontext zum Beispiel den Arbeitsplatz eines Werkers. Sie beobachten ihn bei seiner Tätigkeit, führen Messungen durch und untersuchen die erlangten Daten. Nach der Analyse präsentieren sie ihre Erkenntnisse Dritten (bspw. im Rahmen eines Workshops), dem Management und den Werkern. Insbesondere wenn es um die Auswertung über einen längeren Zeitraum geht (eine ganze Schicht oder mehrere Arbeitszyklen) sind gute Visualisierungen Mangelware und beschränken sich häufig nur auf einfache Linien- oder Balkendiagramme. Um den Ergonomen ihre Tätigkeit zu erleichtern, wurde ein Programm entwickelt, dass die ergonomischen Probleme in einer einfachen Weise als Gesamtüberblick dargestellt. Es ist hierbei möglich von der groben Übersicht aller kritischen Situationen bis hin zu einer detaillierten Ansicht eines Einzelfalls zu navigieren. Ungünstige Posen werden als Piktogramme in Form digitaler Menschmodelle repräsentiert und ermöglichen somit eine intuitive Darstellung. Die Visualisierung berücksichtigt mehrere Methoden aus dem Umfeld der Ergonomie. Eine Methode ist zum Beispiel RULA (Rapid Upper Limb Assessment). Hier wird eine statische Pose des Werkers betrachtet, sozusagen eine Momentaufnahme bei der Ausübung seiner Arbeit. Es basiert auf der Betrachtung der Gelenkwinkel und berücksichtigt zusätzlich Gewichte und Kräfte, die der Werker zu tragen hat beziehungsweise die er aufbringen muss. Darüber hinaus werden auch Anzeichen grenzwertiger Arbeitsumweltfaktoren dargestellt. Die finale interaktive Visualisierung wurde während des gesamten Entwicklungsprozesses in unterschiedlichen Studien evaluiert. Dies beinhaltet unter anderem die Erfassung der Benutzeranforderungen durch Expertenbefragungen, iteratives Prototyping und einer abschließenden Benutzbarkeitsstudie. / Ergonomics deals with the analysis and design of work processes. To identify ergonomically critical situations, appropriate evaluation options have to be developed to enable an efficient analysis process. Nowadays, such analyses are typically carried out with the help of digital models of the surrounding area and virtual humans. These produce a multitude of geo-referenced and time-oriented data. A design study was conducted on how to visualize this data to support the ergonomically analysis process optimally. We propose a novel interactive visualization which provides the user an overview of ergonomically critical situations and their causes. Simultaneously, the user obtains the main stress factors in a compressed form by a glyph-based visual design. During the implementation of the prototype, usability and ergonomics experts were consulted and their suggestions were included in the development of the system. Final expert interviews and a usability study depict the utility of the proposed visualization tool.

A pesquisa busca alcançar novos aportes para estudos em infografia jornalística à medida que investiga qualidades, atividades profissionais e tecnologias envolvidas na produção de uma modalidade infográfica emergente, o infovis, contextualizada pelas potencialidades do meio digital e on-line, e sintonizada com práticas comunicacionais contemporâneas, que supera, em determinados aspectos, modelos infográficos anteriores. Com vistas a atingir nosso objetivo investigativo adotamos metodologia de pesquisa em duas etapas: 1) revisão conceitual de três referências teóricas fundamentais - visualização da informação, infografia jornalística e interatividade; e 2) proposta de análise de infovis com base na técnica de pesquisa de análise de conteúdo. Assim, o corpus empírico é constituído por 270 infovis de conteúdo temático político, sobretudo eleitoral, de quatro sítios jornalísticos - The New York Times, The Guardian, Folha de S. Paulo e O Estado de S. Paulo - veiculados entre jan. 2010 e dez. 2013. A partir de sistemático procedimento de análise elaborado segundo unidades e subunidades analíticas orientadas pelas três dimensões teóricas do dispositivo infovis (input, interface e output), obtivemos respostas codificadas para todas as peças do corpus. A leitura do formulário de análise preenchido gerou resultados e inferências sobre nossa amostra que apontam para aspectos produtivos pioneiros em infografia, como maior abertura comunicacional à audiência, emprego de ferramentas on-line e gratuitas para produção de infovis e utilização de tecnologia de atualização contínua dos dados visualizados. / The research seeks to offer new contributions for studies on journalistic infographics by investigating the qualities, professional activities, and technologies involved in the production of an emerging form of infographics, the infovis, within the context of the potential of online environments, in synch with contemporary communications practices, and which overcomes, in certain aspects, previous infographics models. In order to meet our research objective, we employed a two-stage method: 1) conceptual review of three fundamental theoretical subjects - information visualization, journalistic infographics, and interactivity; and 2) a proposal for the analysis of infovis based on the technique of content analysis research. Thus, the empirical corpus is made up of 270 examples of infovis with political thematic content, mainly electoral, from four journalistic websites - The New York Times, The Guardian, Folha de S. Paulo and O Estado de S. Paulo - published between January 2010 and December 2013. Based on a systematic procedure for analysis, organized by analytical units and subunits, as well as by the three theoretical facets of the infovis device (input, interface and output), we obtained codified responses for all pieces within the corpus. From the reading of the completed analysis form, results and inferences were generated for our sample, which point to pioneering productive features in infographics, such as greater communicative openness with the audience, use of free online tools for the production of infovis, and use of real-time technology for on-screen data

Dreidimensionale Informationsvisualisierungen fördern durch den geringen Grad an Abstraktion die Bildung eines präzisen mentalen Modells und können daher multidimensionale räumliche Beziehungen greifbar kommunizieren. Gleichzeitig eröffnet die aktuelle Generation von Augmented Reality Head-Mounted Displays (AR-HMDs) neuartige Möglichkeiten zur Exploration von 3D-InfoVis und ist befähigt virtuelle Objekte glaubwürdig und immersiv in die physische Umgebung eines Nutzers zu integrieren. Dennoch unterliegt die Interaktion in AR-Umgebungen einer Vielzahl von Herausforderungen, da die signifikante Mehrheit der Applikationen lediglich Blick-, Freihandgesten- oder Sprachsteuerung als Eingabemodalität in Betracht ziehen. Durch Kombination von interaktiven Oberflächen wie Tabletops mit AR-HMDs können diese Nachteile effizient adressiert werden, indem direkte und natürliche Manipulation in Form von Multi-Touch, Tangible- oder Stift-Eingabe ermöglicht wird. Im Rahmen dieser Thesis wird untersucht, wie die Analyse von 3D-InfoVis bei Kombination interaktiver Oberflächen mit AR-HMDs unterstützt werden kann. Hierfür wird der aktuelle Stand der Forschung in themennahen Domänen erfasst und folgend Konzepte zur Unterstützung analytischer Prozesse in zuvor erläuterter Systemkonstellation entwickelt. Die resultierenden Konzepte adressieren dabei Limitationen, die bei Darstellung und Interaktion von und mit 3D-InfoVis in konventionellen Systemen bestehen und im Rahmen der Kombination interaktiver Oberflächen mit AR-HMDs gelöst oder wesentlich angereichert werden können. Ausgewählte Features wurden in einer prototypischen Implementierung realisiert und getestet. / Three-dimensional information visualizations aid precise mental models and are able to communicate multidimensional-spatial relations due too their low level of abstraction. Simultaneously the current generation of Augmented Reality head-mounted displays (AR-HMDs) are offering novel chances for the exploration of 3D-InfoVis and are capable of immersively integrating virtual object into the physical environment of a user. Nevertheless, interaction in AR-environments is still posing a major challenge due to most applications only considering gaze, freehand gesture or speech as input modalities. By combining AR-HMDs with interactive surfaces these limitations can be addressed and direct and natural interaction in the form of multi-touch-, tangible- or pen-input can be enabled. In the scope of this thesis it will be examined how the analysis of 3D-InfoVis can be supported in the context of combining interactive surfaces with AR-HMDs. Therefor the current state of research in associated domains is being summarized and based on that concepts for supporting analytical processes in aforementioned system constellation are being developed. The resulting concepts help addressing limitations, that exist in the representation and interaction of and with 3D-InfoVis in conventional systems in the scope of combining interactive surfaces with AR-HMDs in order to overcome them or reduce their effects. Selected features were implemented and tested in a prototype.

A pesquisa busca alcançar novos aportes para estudos em infografia jornalística à medida que investiga qualidades, atividades profissionais e tecnologias envolvidas na produção de uma modalidade infográfica emergente, o infovis, contextualizada pelas potencialidades do meio digital e on-line, e sintonizada com práticas comunicacionais contemporâneas, que supera, em determinados aspectos, modelos infográficos anteriores. Com vistas a atingir nosso objetivo investigativo adotamos metodologia de pesquisa em duas etapas: 1) revisão conceitual de três referências teóricas fundamentais - visualização da informação, infografia jornalística e interatividade; e 2) proposta de análise de infovis com base na técnica de pesquisa de análise de conteúdo. Assim, o corpus empírico é constituído por 270 infovis de conteúdo temático político, sobretudo eleitoral, de quatro sítios jornalísticos - The New York Times, The Guardian, Folha de S. Paulo e O Estado de S. Paulo - veiculados entre jan. 2010 e dez. 2013. A partir de sistemático procedimento de análise elaborado segundo unidades e subunidades analíticas orientadas pelas três dimensões teóricas do dispositivo infovis (input, interface e output), obtivemos respostas codificadas para todas as peças do corpus. A leitura do formulário de análise preenchido gerou resultados e inferências sobre nossa amostra que apontam para aspectos produtivos pioneiros em infografia, como maior abertura comunicacional à audiência, emprego de ferramentas on-line e gratuitas para produção de infovis e utilização de tecnologia de atualização contínua dos dados visualizados. / The research seeks to offer new contributions for studies on journalistic infographics by investigating the qualities, professional activities, and technologies involved in the production of an emerging form of infographics, the infovis, within the context of the potential of online environments, in synch with contemporary communications practices, and which overcomes, in certain aspects, previous infographics models. In order to meet our research objective, we employed a two-stage method: 1) conceptual review of three fundamental theoretical subjects - information visualization, journalistic infographics, and interactivity; and 2) a proposal for the analysis of infovis based on the technique of content analysis research. Thus, the empirical corpus is made up of 270 examples of infovis with political thematic content, mainly electoral, from four journalistic websites - The New York Times, The Guardian, Folha de S. Paulo and O Estado de S. Paulo - published between January 2010 and December 2013. Based on a systematic procedure for analysis, organized by analytical units and subunits, as well as by the three theoretical facets of the infovis device (input, interface and output), we obtained codified responses for all pieces within the corpus. From the reading of the completed analysis form, results and inferences were generated for our sample, which point to pioneering productive features in infographics, such as greater communicative openness with the audience, use of free online tools for the production of infovis, and use of real-time technology for on-screen data

Dreidimensionale Informationsvisualisierungen fördern durch den geringen Grad an Abstraktion die Bildung eines präzisen mentalen Modells und können daher multidimensionale räumliche Beziehungen greifbar kommunizieren. Gleichzeitig eröffnet die aktuelle Generation von Augmented Reality Head-Mounted Displays (AR-HMDs) neuartige Möglichkeiten zur Exploration von 3D-InfoVis und ist befähigt virtuelle Objekte glaubwürdig und immersiv in die physische Umgebung eines Nutzers zu integrieren. Dennoch unterliegt die Interaktion in AR-Umgebungen einer Vielzahl von Herausforderungen, da die signifikante Mehrheit der Applikationen lediglich Blick-, Freihandgesten- oder Sprachsteuerung als Eingabemodalität in Betracht ziehen. Durch Kombination von interaktiven Oberflächen wie Tabletops mit AR-HMDs können diese Nachteile effizient adressiert werden, indem direkte und natürliche Manipulation in Form von Multi-Touch, Tangible- oder Stift-Eingabe ermöglicht wird. Im Rahmen dieser Thesis wird untersucht, wie die Analyse von 3D-InfoVis bei Kombination interaktiver Oberflächen mit AR-HMDs unterstützt werden kann. Hierfür wird der aktuelle Stand der Forschung in themennahen Domänen erfasst und folgend Konzepte zur Unterstützung analytischer Prozesse in zuvor erläuterter Systemkonstellation entwickelt. Die resultierenden Konzepte adressieren dabei Limitationen, die bei Darstellung und Interaktion von und mit 3D-InfoVis in konventionellen Systemen bestehen und im Rahmen der Kombination interaktiver Oberflächen mit AR-HMDs gelöst oder wesentlich angereichert werden können. Ausgewählte Features wurden in einer prototypischen Implementierung realisiert und getestet.:Einleitung Verwandte Arbeiten Konzept der Augmented Displays Konzepte zur Unterstützung analytischer Prozesse im Umgang mit 3D-InfoVis bei Kombination interaktiver Oberflächen mit AR-HMDs Implementierung Diskussion Zusammenfassung / Three-dimensional information visualizations aid precise mental models and are able to communicate multidimensional-spatial relations due too their low level of abstraction. Simultaneously the current generation of Augmented Reality head-mounted displays (AR-HMDs) are offering novel chances for the exploration of 3D-InfoVis and are capable of immersively integrating virtual object into the physical environment of a user. Nevertheless, interaction in AR-environments is still posing a major challenge due to most applications only considering gaze, freehand gesture or speech as input modalities. By combining AR-HMDs with interactive surfaces these limitations can be addressed and direct and natural interaction in the form of multi-touch-, tangible- or pen-input can be enabled. In the scope of this thesis it will be examined how the analysis of 3D-InfoVis can be supported in the context of combining interactive surfaces with AR-HMDs. Therefor the current state of research in associated domains is being summarized and based on that concepts for supporting analytical processes in aforementioned system constellation are being developed. The resulting concepts help addressing limitations, that exist in the representation and interaction of and with 3D-InfoVis in conventional systems in the scope of combining interactive surfaces with AR-HMDs in order to overcome them or reduce their effects. Selected features were implemented and tested in a prototype.:Einleitung Verwandte Arbeiten Konzept der Augmented Displays Konzepte zur Unterstützung analytischer Prozesse im Umgang mit 3D-InfoVis bei Kombination interaktiver Oberflächen mit AR-HMDs Implementierung Diskussion Zusammenfassung

Dans un contexte de données industrielles et numériques, le développement d'un outil sur mesure pour une tâche particulière est couteux par de nombreux aspects. À l'inverse, l'adaptation d'outils génériques l'est également en particularisation (personnalisation, adaptation, extension, …), pour les développeurs comme pour les utilisateurs finaux. Nos approches visent à considérer les différents niveaux d'interactions pour améliorer l'exploitation des données fournies ou générées en collaboration.Les définitions et problématiques liées aux données dépendent le plus souvent des domaines dans lesquelles elles sont traitées. Pour ce travail, nous avons opté pour une approche holistique considérant ensemble des perspectives différentes. Le résultat est une synthèse des concepts émergeant montrant les équivalences d'un domaine à l'autre. La première contribution consiste à améliorer le marquage collaboratif de documents. Deux améliorations sont proposées par notre outil Coviz. (1) L'étiquetage des ressources est propre à chaque utilisateur qui organise ses vocables par une poly-hiérarchie nominative. Chacun peut considérer les concepts des autres par une relation de partage. Le système fournit également du contenu connexe via un moissonnage des archives ouvertes. (2) L'outil applique le concept de facette des données à l'interface puis les combine avec une recherche par mot-clé. Ce dernier point est commun à tous les utilisateurs, le système considère chacune des actions individuelles comme celles d'un groupe.La contribution majeure, confidentielle, est un framework baptisé DIP pour Data Interaction and Presentation. Son but est d'augmenter la liberté d'expression de l'utilisateur sur l'interaction et l'accès aux données. Il diminue les contraintes machines et logicielles en adjoignant une nouvelle voix d'accès direct entre l'utilisateur et les données disponibles, ainsi que des points d'« articulation » génériques. D'un point de vue final, l'utilisateur gagne en expression de filtrage, en partage, en maintien de l'état de sa navigation, en automatisation de ses tâches courantes, etc.Il a été testé en condition réelle de stress, de ressources et d'utilisation avec le logiciel KeePlace. Ce dernier a d'ailleurs été l'initiateur de cette thèse. / In the context of numeric data, the software development costs entail a number of cost factors. In contrast, adapting generic tools has its own set of costs, requiring developer's integration and final user's adaptation. The aim of our approach is to consider the different points of interaction with the data to improve the exploitation of data, whether provided or generated from collaboration.The definitions and problems related to data are dependent upon the domain from which the data come and the treatment that have been applied to them. In this work we have opted for a holistic approach where we consider the range of angles. The result is a summary of the emergent concepts and domain equivalences.The first contribution consists of improving collaborative document mark-up. Two improvements are proposed by out tool – Coviz –. 1) Resource tagging which is unique to each user, who organises their own labels according to their personal poly-hierarchy. Each user may take into consideration other users approaches through sharing of tags. The system supplies additional context through a harvesting of documents in open archives. 2) The tool applies the concept of facets to the interface and then combines them to provide a search by keyword or characteristic selection. This point is shared by all users and the actions of an individual user impact the whole group.The major contribution, which is confidential, is a framework christened DIP for Data Interaction and Presentation. Its goal is to increase the freedom of expression of the user over the interaction and access to data. It reduces the hardware and software constrains by adding a new access point between the user and the raw data as well as generic pivots. From a final point of view the user gains in expression of filtering, in sharing, in state persistence of the navigator, in automation of day-to-day tasks, etc.DIP has been stress tested under real-life conditions of users and limited resources with the software KeePlace. Acknowledgement is given to KeePlace who initiated this thesis.

The amount of data that is available to us is ever increasing, and thus is the potential to extract information from it. Information visualization, which leverages our perceptual system to enable us to perceive patterns, outliers, trends and anomalies in large amounts of data, is an important technique for exploratory data analysis. As part of a flexible visual data analysis process, the user needs to construct and parametrize visualizations, which is challenging for novice users. In this thesis, I explore how information visualization novices can be supported in visualization construction. First, I identify existing visualization construction approaches in a systematic literature survey and examine their use cases. Second, I conduct a laboratory study to learn about the process and the characteristics of how information visualization novices construct visualization during data analysis. Third, I identify natural language visualization queries as a promising alternative specification approach that I study by analyzing the queries from the laboratory experiment and by conducting an online survey study. Based on my findings, I propose a descriptive model of natural language visualization queries. Fourth, I derive guidelines for visualization construction tools from my studies and from related work. Finally, I show how these guidelines can be applied to existing visualization tools using the example of the Choosel visualization framework. / Graduate