This thesis introduces a music visualization system for stereophonic source separated music. Music visualization systems are a popular way to represent information from audio signals through computer graphics. Visualization can help people better understand music and its complex and interacting elements. This music visualization system extracts pitch, panning, and loudness features from source separated audio files to create the visual. Most state-of-the art visualization systems develop their visual representation of the music from either the fully mixed final song recording, where all of the instruments and vocals are combined into one file, or from the digital audio workstation (DAW) data containing multiple independent recordings of individual audio sources. Original source recordings are not always readily available to the public so music source separation (MSS) can be used to obtain estimated versions of the audio source files. This thesis surveys different approaches to MSS and music visualization as well as introduces a new music visualization system specifically for source separated music.

Prostatacancer är en vanligt förekommande sjukdom i Sverige. För att få bukt med sjukdomen krävs att mer resurser sätts in för att effektivisera forskningen inom området. Ett samarbete mellan Karolinska Institutet, Kungliga Tekniska Högskolan och Janssen- Cilag AB har resulterat i LUPA, ett informationsvisualiseringssystem, med ambitionen att åstadkomma en effektivare process för hypotesgenerering gällande prostatacancer. Det här projektet handlar om att validera systemets funktion för den tilltänkta målgruppen; det vill säga att göra hypotesgenereringsprocessen enklare och mer effektiv för forskare som arbetar med prostatacancerdata i Stockholms län. Från resultatet kan man se att ett informationsvisualiseringsverktyg skulle vara användbart för att effektivisera dagens cancerforskningsprocess. Tidsåtgången för nystartade projekts första grundläggande steg skulle kunna reduceras drastiskt, särskilt stegen för införskaffning av data och datamanipulation. Dessutom upplevdes systemet främja hypotesgenereringsprocessen genom enkelheten att kvickt generera nya visuella strukturer för olika variabler. Slutligen visade det här projektet att organiserad och ren rådata är sällsynt. Testdeltagarna uppskattade informationsvisualiseringen men såg mest potential i dess möjlighet att städa och strukturera data. / Prostate cancer is a common disease in Sweden. In order to overcome the disease, more resources must be invested to streamline research in the field. A collaboration between Karolinska Institutet, the Royal Institute of Technology and Janssen-Cilag AB has resulted in LUPA, an information visualization system with the ambition of achieving a more efficient process for hypothesis generation regarding prostate cancer. This thesis project is about validating the system's function for the intended target group; that is, to make the hypothesis generation process simpler and more efficient for researchers working with prostate cancer data in Stockholm County. From the results, it can be seen that an information visualization tool would be useful to streamline the current cancer research process. The time required for the first basic steps of new projects could be drastically reduced, especially the steps for data acquisition and data manipulation. In addition, the system was perceived to promote the hypothesis generation process through the simple methods of quickly generating new visual structures for different variables. Finally, this project showed that organized and clean raw data is rare. The test participants appreciated the information visualization but saw the most potential in its ability to clean and structure data.

Awareness of anthropogenic climate change has increased drastically in the last decade. With the help of the United Nations and the 17 sustainable development goals, there is now an international consensus that measures must be taken urgently. Actions towards reducing our climate impact have started to take place in various industries and one important sector is the food sector. This thesis is addressed to companies that help consumers make smarter and more climate friendly food decisions with the help of climate data. More specifically the scope of this thesis was to develop and evaluate a climate impact visualization application with consumers as the intended target group. The foundation of the intervention included theories in behaviour change and information visualization design principles. The application was evaluated with 11 participants looking to reduce their climate impact. A user study was conducted where the participants used the developed intervention by completing different tasks and then evaluated the experience and the different components of the application. The purpose of the evaluation was to gain qualitative insights of which components should be considered in the development process of a final product. The results indicate that visualizations of the products carbon dioxide emissions, receipt list and personal progress tracking were the most important components for the application. The result also gave positive indications that a similar application could help change the user’s behaviour when purchasing food to a more climate friendly pattern. / Medvetenheten om antropogena klimatförändringar har ökat drastiskt under det senaste decenniet. Med hjälp av FN och de 17 målen för hållbar utveckling finns det nu en internationell enighet om att åtgärder måste vidtas snarast. Åtgärder för att minska vår klimatpåverkan har börjat äga rum i olika branscher och en viktig sektor är livsmedelssektorn. Denna avhandling riktar sig till företag som hjälper konsumenter att fatta smartare och mer klimatvänliga livsmedelsbeslut med hjälp av klimatdata. Mer specifikt omfattar denna avhandling att utveckla och utvärdera en visualiseringsapplikation för klimatpåverkan med konsumenter som den avsedda målgruppen. Grunden för interventionen inkluderar teorier inom beteendeförändring och design-principer för informationsvisualisering. Applikationen utvärderades med 11 deltagare som ville minska sin klimatpåverkan. En användarstudie genomfördes där deltagarna använde den utvecklade applikationen genom att utföra olika uppgifter för att sedan utvärdera upplevelsen och de olika komponenterna i applikationen. Syftet med utvärderingen var att få kvalitativa insikter om vilka komponenter som bör beaktas i utvecklingsprocessen för en slutprodukt. Resultaten indikerar att visualiseringar av produkternas koldioxidutsläpp, kvittolista och personlig framstegsspårning var de viktigaste komponenterna för applikationen. Resultatet gav också positiva indikationer på att en liknande applikation skulle kunna hjälpa till att ändra användarens beteende när man handlar mat till ett mer klimatvänligt mönster.

[pt] O crescimento cada vez mais acelerado da produção de dados e a decorrente necessidade de explorá-los a fim de se obter respostas para as mais variadas perguntas têm promovido o desenvolvimento de ferramentas que visam a facilitar a manipulação e a construção de gráficos. Essas visualizações devem permitir explorar os dados de maneira efetiva, comunicando as informações com precisão e possibilitando um maior ganho de conhecimento. No entanto, construir boas visualizações de dados não é uma tarefa trivial, uma vez que pode requerer um grande número de decisões que, em muitos casos, exigem certa experiência por parte de seu projetista. Visando a facilitar o processo de exploração de conjuntos de dados através da construção de visualizações, nós desenvolvemos a ferramenta VisMaker, que utiliza um conjunto de regras para construir as visualizações consideradas mais apropriadas para um determinado conjunto de variáveis. Além de permitir que o usuário defina visualizações através do mapeamento entre variáveis e dimensões visuais, o VisMaker apresenta recomendações de visualizações organizadas através de perguntas construídas com base nas variáveis selecionadas pelo usuário, objetivando facilitar a compreensão das visualizações recomendadas e auxiliando o processo exploratório. Para a avaliação do Vis- Maker, nós realizamos dois estudos comparando-o com o Voyager 2, uma ferramenta de propósito similar existente na literatura. O primeiro estudo teve foco na resolução de perguntas enquanto que o segundo esteve voltado para a exploração de dados em si. Nós analisamos alguns aspectos da utilização das ferramentas e coletamos os comentários dos participantes, através dos quais pudemos identificar vantagens e desvantagens da abordagem de recomendação que propusemos, levantando possíveis melhorias para esse tipo de ferramenta. / [en] The increasingly rapid growth of data production and the consequent need to explore them to obtain answers to a wide range of questions have promoted the development of tools to facilitate the manipulation and construction of data visualizations. These tools should allow users to effectively explore data, communicate information accurately, and enable more significant knowledge gain through data. However, building useful data visualizations is not a trivial task: it may involve a large number of decisions that often require experience from their designer. To facilitate the process of exploring datasets through the construction of visualizations, we developed VisMaker, a software tool which uses a set of rules to determine appropriate visualizations for a certain selection of variables. In addition to allowing the user to define visualizations by mapping variables onto visualization channels, VisMaker presents visualization recommendations organized through questions constructed based on the variables selected by the user, trying to facilitate the understanding of the visualization recommendations and assisting the exploratory process. To evaluate VisMaker, we carried out two studies comparing it with another tool that exists in the literature, one aimed at solving questions and the other at data exploration. We analyzed some aspects of the use of the tools. We collected feedback from the participants, through which we were able to identify the advantages and disadvantages of the recommendation approach we proposed, raising possible improvements for this type of tool.

Read some more and check the prototypes at http://www.stiber.se/commonfate.html. / War Memorials are often forgotten statues, right in the center of town, but still out of our sight. They do not tell you enough to understand them, neither are you interested in putting effort into getting to know and learn from them. This paper investigates how the web could be used to create a war memorial that is more alive, captivating and empathy awakening. There has been some virtual war memorials getting constructed since the web started to bloom, but we could not find a single one that had actually fully explored the potential of the web, and what it might have to offer for the creation of war memorials. Researching the web as a media, experience design, and information visualization, we find possibilities to mourn, commemorate and heal on virtual ground. Inspiring reflection and contemplation are another two purposes of The Common Fate Memorial. War memorial studies give us the background information needed, and ceremony mechanics are studied for further inspiration. Our findings are implemented in flash prototypes, which are user tested and evaluated.

It is a challenging task for interaction designers to find a way to design a digital artefact supporting serendipitous discovery. Its interdisciplinary nature requires sufficient knowledge of information visualization, social navigation and serendipity. Based on literature review and prior relevant works, several traces having potential to aid such exploration were defined. Through creating and testing AniMap, an interactive graph visualization for discovering new anime clips, in this thesis I argue that such an artefact has the potential to support serendipitous discovery, owing to its features of being information visualization, interactive and in a graph layout, coupled with users’ personal interests. Even so, finding details of how to influence serendipitous discovery remain an ongoing challenge considering the dynamic nature of serendipity.

Search engines make vast amounts of information available to Internet users. Two types of tasks users engage in using search engines are closed-ended and open-ended. For closed-ended tasks, individuals have narrow objectives that require finding specific results. For open-ended tasks, individuals only have general objectives that require finding as much relevant information as possible about a topic, which can be difficult when large numbers of both relevant and irrelevant results are returned from a query. This can also leave users in a state of information overload. Some search engines have incorporated information visualization techniques (combining cognitive senses with visual cues that allow for better understanding the information) to facilitate browsing through results in order to reduce information overload. However, there is little research that identifies which visual cues are the most desirable for the presentation of search results. According to information foraging theory, cues that have strong scents will help users find information faster. In this study, we investigate the effects of augmenting visualizations with animation as a powerful scent to help users more easily identify relevant information in search engine results. This study employs cognitive fit theory to study the effect of different information formats on users' performance in completing the two different tasks. Overall, we find evidence that the effectiveness of cues such as animation is task-dependent. For example, we find that visualizations with animation are less effective than a standard textual display for subjects performing closed-ended web search tasks. The results of this study have strong implications for integrating appropriate cues into visualizations in order to help people find information. / Business Administration

Much computer communications activity is invisible to the user, happening without explicit permission. When system administrators investigate network communications activities, they have difficulty tracing them back to the processes that cause them. The strictly layered TCP/IP networking model that underlies all widely used, general-purpose operating systems makes it impossible to trace a packet seen on the network back to the processes that are responsible for generating and receiving it. The TCP/IP model separates the concerns of network routing and process ownership so that the layers cannot share the information needed to correlate packets to processes. But knowing what processes are responsible for communications activities can be a great help in determining whether that activity is benign or malicious. My solution combines a visualization tool, a kernel-level correlation engine, and middleware that ties the two together. My research enables security personnel to visually correlate packets to the processes they belong to helping users determine whether communications are benign or malicious. I present my discoveries about the system administrator community and relate how I created a new correlation technology. I conducted a series of initial interviews with system administrators to clarify the problem, researched available solutions in the literature, identified what was missing, and worked with users to build it. The users were my co-designers as I built a series of prototypes of increasing fidelity and conducted usability evaluations on them. I hope that my work will demonstrate how well the participatory design approach works. My work has implications for the kernel structure of all operating system kernels with a TCP/IP protocol stack and network model. In light of my research, I hope security personnel will more clearly see sets of communicating processes on a network as basic computational units rather than the individual host computers. If kernel designers incorporate my findings into their work, it will enable much better security monitoring than is possible today making the Internet safer for all. / Ph. D.

Topic management is the task of gathering, evaluating, organizing, and sharing a set of web sites for a specific topic. Current web tools do not provide adequate support for this task. We created and continue to develop the TopicShop system to address this need. TopicShop includes (1) a web crawler/analyzer that discovers relevant web sites and builds site profiles, and (2) user interfaces for information workspaces. We conducted an empirical pilot study comparing user performance with TopicShop vs. Yahooï . Results from this study were used to improve the design of TopicShop. A number of key design changes were incorporated into a second version of TopicShop based on results and user comments of the pilot study including (1) the tasks of evaluation and organization are treated as integral instead of separable, (2) spatial organization is important to users and must be well supported in the interface, and (3) distinct user and global datasets help users deal with the large quantity of information available on the web. A full empirical study using the second iteration of TopicShop covered more areas of the World Wide Web and validated results from the pilot study. Across the two studies, TopicShop subjects found over 80% more high-quality sites (where quality was determined by independent expert judgements) while browsing only 81% as many sites and completing their task in 89% of the time. The site profile data that TopicShop provide -- in particular, the number of pages on a site and the number of other sites that link to it -- were the key to these results, as users exploited them to identify the most promising sites quickly and easily. We also evaluated a number of link- and content-based algorithms using a dataset of web documents rated for quality by human topic experts. Link-based metrics did a good job of picking out high-quality items. Precision at 5 (the common information retrieval metric indicating the percentage of high quality items selected that are actually high quality) is about 0.75, and precision at 10 is about 0.55; this is in a dataset where 32% of all documents were of high quality. Surprisingly, a simple content-based metric, which ranked documents by the total number of pages on their containing site, performed nearly as well. These studies give insight into users' needs for the task of topic management, and provide empirical evidence of the effectiveness of task-specific interfaces (such as TopicShop) for managing topical collections. / Ph. D.

Visualization tools allow scientists to comprehend very large data sets and to discover relationships which are otherwise difficult to detect. Unfortunately, not all types of data can be visualized easily using existing tools. In particular, long sequences of nonnumeric data cannot be visualized adequately. Examples of this type of data include trace files of computer performance information, the nucleotides in a genetic sequence, a record of stocks traded over a period of years, and the sequence of words in this document. The term categorical time series is defined and used to describe this family of data. When visualizations designed for numerical time series are applied to categorical time series, the distortions which result from the arbitrary conversion of unordered categorical values to totally ordered numerical values can be profound. Examples of this phenomenon are presented and explained. Several new, general purpose techniques for visualizing categorical time series data have been developed as part of this work and have been incorporated into the Chitra perfor- mance analysis and visualization system. All of these new visualizations can be produced in O(n) time. The new visualizations for categorical time series provide general purpose techniques for visualizing aspects of categorical data which are commonly of interest. These include periodicity, stationarity, cross-correlation, autocorrelation, and the detection of recurring patterns. The effective use of these visualizations is demonstrated in a number of application domains, including performance analysis, World Wide Web traffic analysis, network routing simulations, document comparison, pattern detection, and the analysis of the performance of genetic algorithms. / Ph. D.