La théorie de l'information a influencé un grand nombre de domaines scientifiques depuis son introduction par Claude Shannon en 1948. A part la loi de Fitts et la loi de Hick, qui sont apparus lorsque les psychologues expérimentaux étaient encore enthousiastes à l'idée d'appliquer la théorie de l'information aux différents domaines de la psychologie, les liens entre la théorie de l'information et l'interaction humain-machine (IHM) ont été peu explorés. L'objectif de cette thèse est de combler le fossé entre la théorie de l'information et l'IHM en considérant que l'interaction entre les humains et les machines peut être considérée comme un processus de communication et peut donc être caractérisée à l'aide des concepts de la théorie de l'information. Les trois principales contributions de cette thèse sont : (1) une perspective historique détaillée sur la manière dont la théorie de l'information a influencé la psychologie et l'IHM, avec en particulier une discussion approfondie et une analyse de la pertinence de la loi de Hick pour l'IHM, (2) le cadre formel Gain d'Information Bayésienne (BIG pour Bayesian Information Gain) qui quantifie et exploite les informations envoyées par l'utilisateur à l'ordinateur pour exprimer son intention et (3) une illustration des avantages de l'utilisation des mesures de la théorie de l'information pour évaluer la performance des entrées et pour caractériser une tâche d'interaction. Cette thèse démontre ainsi que la théorie de l'information peut être utilisée comme un outil unifié pour comprendre et concevoir la communication et l'interaction humain-machine. / Information theory has influenced a large number of scientific fields since its first introduction in 1948. Apart from Fitts' law and Hick's law, which came out when experimental psychologists were still enthusiastic about applying information theory to various areas of psychology, the relation between information theory and human-computer interaction (HCI) has rarely been explored. This thesis strives to bridge the gap between information theory and HCI by taking the stance that human-computer interaction can be considered as a communication process and therefore can be characterized using information-theoretic concepts. The three main contributions are: (1) a detailed historical perspective on how information theory influenced psychology and HCI, particularly an in-depth discussion and analysis of how relevant Hick's law is to HCI; (2) a Bayesian Information Gain (BIG) framework that quantifies the information sent by the user to the computer to express her intention; and (3) a further illustration of the advantages of using information-theoretic measures to evaluate input performance and to characterize the rich aspects of an interaction task. This thesis demonstrates that information theory can be used as a unified tool to understand and design human-computer communication.

The study examines the differences between women’s and men’s perception of visual aesthetics on Pinterest. Therefore, we have chosen to examine the visual aesthetics through the lens of simplicity, diversity, colour and craftmanship. The purpose of the study is to contribute to a deeper understanding of the perception of visual aspects between men and women on the social media platform Pinterest. As society grows and develops on a variety of levels, we humans must increasingly adapt to a higher pace of life. A higher pace of life can mean that we as humans are forced to have a greater focus on where we spend our time and what we choose to focus our attention on. This indicates that people in today's society and in their everyday lives must decide which social media they choose to pay attention to. We ask ourselves the question: How do people do when they must distribute time and attention over social media? What factors drive these decisions? Are men and women attracted to different factors? After studying the results, we were able to conclude that female participants valued Pinterest as less aesthetically pleasing than the male participants did. Finally, we would like to point out that even though the majority of users are women on Pinterest, our study shows that men value the visual aesthetics higher than women.

Information technology (IT) investment decision makers are required to process large volumes of complex data. An existing body of knowledge relevant to IT portfolio management (PfM), decision analysis, visual comprehension of large volumes of information, and IT investment decision making suggest Multi-Criteria Decision Making (MCDM) and hypervariate display techniques can reduce cognitive load and improve decision confidence in IT PfM decisions. This dissertation investigates improving the decision confidence by reducing cognitive burden of the decision maker through greater comprehension of relevant decision information. Decision makers from across the federal government were presented with actual federal IT portfolio project lifecycle costs and durations using hypervariate displays to better comprehend IT portfolio information more quickly and make more confident decisions. Other information economics attributes were randomized for IT portfolio projects to generate Balanced Scorecard (BSC) values to support MCDM decision aids focused on IT investment alignment with specific business objectives and constraints. Both quantitative and qualitative measures of participant comprehension, confidence, and efficiency were measured to assess hypervariate display treatment and then MCDM decision aid treatment effectiveness. Morae Recorder Autopilot guided participants through scenario tasks and collected study data without researcher intervention for analysis using Morae Manager. Results showed improved comprehension and decision confidence using hypervariate displays of federal IT portfolio information over the standard displays. Both quantitative and qualitative data showed significant differences in accomplishment of assigned IT portfolio management tasks and increased confidence in decisions. MCDM techniques, incorporating IT BSC, Monte Carlo simulation, and optimization algorithms to provide cost, value, and risk optimized portfolios improved decision making efficiency. Participants did not find improved quality and reduced uncertainty from optimized IT portfolio information. However, on average participants were satisfied and confident with the portfolio optimizations. Improved and efficient methods of delivering and visualizing IT portfolio information can reduce decision maker cognitive load, improve comprehension efficiency, and improve decision making confidence. Study results contribute to knowledge in the area of comprehension and decision making cognitive processes, and demonstrate important linkages between Human-Computer Interaction (HCI) and Decision Support Systems (DSS) to support IT PfM decision making.

Cette thèse traite des interfaces utilisateur tangibles (TUI). La première partie de ce manuscrit concerne l'interaction tangible sur table interactive. Nous introduisons tout d'abord les TUIs et les tables interactives. Nous validons une hypothèse concernant la spécialisation de la forme des interacteurs tangibles et nous en tirons les conséquences pour la conception des TUIs. Nous proposons une solution de boîtier à boutons pour y déporter certaines opérations dans le contexte d'une TUI sur table interactive. Nous abordons la construction et le développement d'un système de tables interactives tangibles transportables et à faible coût permettant de faire du prototypage rapide de TUIs. Nous terminons en soulignant les particularités de l'évaluation expérimentale des TUIs. La seconde partie de ce manuscrit traite un cas d'application d'une TUI pour les géosciences : GeoTUI. Nous commençons par présenter le contexte métier des géophysiciens et leurs besoins en terme de nouveaux moyens d'interaction. Nous présentons les résultats de notre conception d'une TUI pour les géosciences. Nous précisons le détail du développement de notre prototype. Pour terminer, nous présentons les deux expérimentations utilisateurs qui ont été conduites pour valider nos choix de conception. / This thesis focuses on tangible user interfaces (TUI). The first part of this manuscript is about tangible interaction on tabletop. We first introduce TUIs and tabletops. We validate an hypothesis about the specialization of the form of the tangible objects, and conclude from that consequences on TUIs design. We propose the solution of a button box to deport some operations in the context of tabletop TUI. We present the construction and development of a transportable and low cost tabletop TUI system that allows rapid TUI prototyping. We end pointing out the special features of user experiments of TUIs. The second part of this manuscript deals with an application case of a TUI for geoscience: GeoTUI. We start presenting the context of the geophysicists work and their need in term of new way of interation. We present the results of our design of a TUI for geoscience. We detail the development of our prototype. To finish, we present two user experiments we conducted to validate our design choices.

Computerised Cognitive Behavioural Therapy (CCBT) has been recommended for patients in the National Health Service (NHS) Primary Care across the United Kingdom for management of mild to moderate anxiety and depression. This approach also promises financial savings, and may fill the gap between demand and supply of face-to-face therapy. Studies have shown that CCBT is feasible and effective. However, dropout rates can be as high as 86%, but the reasons remain unclear and the information available is limited. This thesis explores factors that may impact on the usability and user experience of this computer-mediated therapy. Espousing the “real world” research philosophy and widely used methods in the Human-Computer Interaction (HCI) field for usability evaluations, four studies using a mixed-methods design were conducted. Study I was an online usability survey, which investigated if usability evaluations had been conducted for CCBT applications. Two versions of questionnaires were sent to four CCBT software developers and ten authors of randomised controlled trials. The categories and responses of the questionnaires gathered from five respondents were reviewed and summarised. The findings suggested that usability evaluations for CCBT were still in their infancy when compared to other healthcare interventions to which HCI approaches have been widely applied. Study II was a usability Heuristic Evaluation (HE) conducted with four expert evaluators to assess two different CCBT applications’ interfaces (MoodGYM and Living Life to the Full) against the self-designed usability heuristics for their compliance. The findings revealed numerous usability issues. Major problems related to navigation and inconsistency of the interfaces were identified. These could be rectified to enhance the user experience. Study III focused on other factors besides usability that might have an influence on the effective use of CCBT. Perceptions of service providers who were involved in both decision-making about CCBT availability and supporting its use were gathered. Nine service providers at different NHS organisations were interviewed. The interviews were analysed using techniques from Grounded Theory (GT). The findings suggested that the practitioners’ attitudes towards CCBT might have affected its service delivery. Four categories from the data analysis were identified: (1) shaping behaviour, (2) implementing and delivering, (3) making an appropriate referral, and (4) technology/CCBT packages - advancing with time. A conceptual model was also generated, “building support around CCBT”: a road-map that could address some of these issues. Study IV examined patients’ perceptions and acceptance of a CCBT application (Beating the Blues), its usability and the user experience, and also whether the user characteristics (e.g. computer experience (CE) and computer self-efficacy (CSE)) had any influence on patients’ use of this technology. A mixed-methods approach was utilised with a sample of 33 participants. Face-to-face and email interviews were conducted. Feedback was also gathered from a usability questionnaire and think-aloud protocol with seven participants selected from the sample. The data were analysed using Thematic and Saliency Analysis to uncover themes. Descriptive statistics were used to describe data from questionnaires. Two overarching themes from the interviews were identified: (1) access to CCBT services, and (2) perceptions and attitudes towards CCBT. Both themes revealed issues which might have significantly impacted on patients’ engagement with CCBT. Numerous flaws were also discovered in the application’s design and functionality (e.g. navigation, aesthetics, relevance of content, and inflexibility). However, the results from CE and CSE questionnaires suggested that participants were confident in using this technology. The four studies provided an in-depth understanding of factors that affect the usability and user experience of CCBT and possible reasons for the high attrition rates. The implications of this research point to the need for health policymakers to focus on the current implementation issues and on how best to deploy this treatment therapy to patients. Further development of CCBT is pivotal to its success, in particular, expanding contexts of use and increasing usability evaluations. Keeping users interested and engaged will improve treatment efficiency, completion rates and will achieve better clinical outcomes.

This dissertation is composed of three studies that use statistical, behavioral, and neuroimaging methods to investigate Chinese and English speakers’ semantic interpretations of four types of visual information including icons, single Chinese characters, single English words, and pictures. The goal is to examine whether people cognitively process icons as logographical words. By collecting survey data from 211 participants, the first study investigated how differently these four types of visual information can express specific meanings without ambiguity on a quantitative scale. In the second study, 78 subjects participated in a behavioral experiment that measured how fast people could correctly interpret the meaning of these four types of visual information in order to estimate the differences in reaction times needed to process these stimuli. The third study employed functional magnetic resonance imaging (fMRI) with 20 participants selected from the second study to identify brain regions that were needed to process these four types of visual information in order to determine if the same or different neural networks were required to process these stimuli. Findings suggest that 1) similar to pictures, icons are statistically more ambiguous than English words and Chinese characters to convey the immediate semantics of objects and concepts; 2) English words and Chinese characters are more effective and efficient than icons and pictures to convey the immediate semantics of objects and concepts in terms of people’s behavioral responses, and 3) according to the neuroimaging data, icons and pictures require more resources of the brain than texts, and the pattern of neural correlates under the condition of reading icons is different from the condition of reading Chinese characters. In conclusion, icons are not cognitively processed as logographical words like Chinese characters although they both stimulate the semantic system in the brain that is needed for language processing. Chinese characters and English words are more evolved and advanced symbols that are less ambiguous, more efficient and easier for a literate brain to understand, whereas graphical representations of objects and concepts such as icons and pictures do not always provide immediate and unambiguous access to meanings and are prone to various interpretations. / text

The use of hand gestures provides an attractive alternative to cumbersome interface devices such as keyboard, mouse, joystick, etc. Hand tracking has a great potential as a tool for better human-computer interaction by means of communication in a more natural and articulate way. This has motivated a very active research area concerned with computer vision-based analysis and interpretation of hand gestures and hand tracking. In this study, a real-time hand tracking system is developed. Mainly, it is image-based hand tracking and based on 2D image information. For separation and identification of finger parts, coloured markers are used. In order to obtain 3D tracking, a stereo vision approach is used where third dimension is obtained by depth information. In order to see results in 3D, a 3D hand model is developed and Java 3D is used as the 3D environment. Tracking is tested on two different types of camera: a cheap USB web camera and Sony FCB-IX47AP camera, connected to the Matrox Meteor frame grabber with a standard Intel Pentium based personal computer. Coding is done by Borland C++ Builder 6.0 and Intel Image Processing and Open Source Computer Vision (OpenCV) library are used as well. For both camera types, tracking is found to be robust and efficient where hand tracking at ~8 fps could be achieved. Although the current progress is encouraging, further theoretical as well as computational advances are needed for this highly complex task of hand tracking.

The field of Human Computer Interaction (HCI) has suggested various methods for evaluating systems in order to improve their usability and User eXperience (UX). The advent of Web 2.0 has allowed the development of applications marked by collaboration, communication and interaction among their users in a way and on a scale never seen before. Social Systems (SS) (e.g. Twitter, Facebook, MySpace, LinkedIn etc.) are examples of such applications and have features such as: frequent exchange of messages, spontaneity and expression of feelings. The opportunities and challenges posed by these types of applications require the traditional evaluation methods to be reassessed, taking into consideration these new characteristics. For instance, the postings of users on SS reveal their opinions on various issues, including on what they think of the system. This work aims to test the hypothesis that the postings of users in SS provide relevant data for evaluation of the usability and of UX in SS. While researching through literature, we have not identified any evaluation model intending to collect and interpret texts from users in order to assess the user experience and system usability. Thus, this thesis proposes MALTU - Model for evaluation of interaction in social systems from the Users Textual Language. In order to provide a basis for the development of the proposed model, we conducted a study of how users express their opinions on the system in natural language. We extracted postings of users from four SS of different contexts. HCI experts classified, studied and processed such postings by using Natural Language Processing (PLN) techniques and data mining, and then analyzed them in order to obtain a generic model. The MALTU was applied in two SS: an entertainment and an educational SS. The results show that is possible to evaluate a system from the postings of users in SS. Such assessments are aided by extraction patterns related to the use, to the types of postings and to HCI factors used in system. / A Ãrea de InteraÃÃo Humano-Computador (IHC) tem sugerido muitas formas para avaliar sistemas a fim de melhorar sua usabilidade e a eXperiÃncia do UsuÃrio (UX). O surgimento da web 2.0 permitiu o desenvolvimento de aplicaÃÃes marcadas pela colaboraÃÃo, comunicaÃÃo e interatividade entre seus usuÃrios de uma forma e em uma escala nunca antes observadas. Sistemas Sociais (SS) (e.g., Twitter, Facebook, MySpace, LinkedIn etc.) sÃo exemplos dessas aplicaÃÃes e possuem caracterÃsticas como: frequente troca de mensagens e expressÃo de sentimentos de forma espontÃnea. As oportunidades e os desafios trazidos por esses tipos de aplicaÃÃes exigem que os mÃtodos tradicionais de avaliaÃÃo sejam repensados, considerando essas novas caracterÃsticas. Por exemplo, as postagens dos usuÃrios em SS revelam suas opiniÃes sobre diversos assuntos, inclusive sobre o que eles pensam do sistema em uso. Esta tese procura testar a hipÃtese de que as postagens dos usuÃrios em SS fornecem dados relevantes para avaliaÃÃo da Usabilidade e da UX (UUX) em SS. Durante as pesquisas realizadas na literatura, nÃo foi identificado nenhum modelo de avaliaÃÃo que tenha direcionado seu foco na coleta e anÃlise das postagens dos usuÃrios a fim de avaliar a UUX de um sistema em uso. Sendo assim, este estudo propÃe o MALTU â Modelo para AvaliaÃÃo da interaÃÃo em sistemas sociais a partir da Linguagem Textual do UsuÃrio. A fim de fornecer bases para o desenvolvimento do modelo proposto, foram realizados estudos de como os usuÃrios expressam suas opiniÃes sobre o sistema em lÃngua natural. Foram extraÃdas postagens de usuÃrios de quatro SS de contextos distintos. Tais postagens foram classificadas por especialistas de IHC, estudadas e processadas utilizando tÃcnicas de Processamento da Linguagem Natural (PLN) e mineraÃÃo de dados e, analisadas a fim da obtenÃÃo de um modelo genÃrico. O MALTU foi aplicado em dois SS: um de entretenimento e um SS educativo. Os resultados mostram que à possÃvel avaliar um sistema a partir das postagens dos usuÃrios em SS. Tais avaliaÃÃes sÃo auxiliadas por padrÃes de extraÃÃo relacionados ao uso, aos tipos de postagens e Ãs metas de IHC utilizadas na avaliaÃÃo do sistema.

Mobile technology is developing quickly and becomming a part of daily life and communication. Bluetooth Low Energy is presented as a new way of mobile interaction. However there are not enough studies in this field on the interaction between mobile devices and the physical world. In order to understand user needs, and to encourage users to interact, we simulated an interaction process through designing and testing a prototype in a specific indoor environment. Prototype effectiveness and main characteristics for future mobile application was evaluated through a qualitative user study with 20 participants who interacted with our prototype. / Den mobila tekniken växer snabbt och blir en del av våra liv och vår kommunikation. BLE presenteras på ett nytt sätt inom mobilinteraktion. Det förekommer inte tillräckligt med studier inom området för interaktionen mellan mobila enheter och den fysiska världen. För att förstå användarbehov och få användare att interagera har vi simulerat en interaktiv process genom att designa och testa en prototyp i en specifik inomhusmiljö. Utvärdering av prototypens effektivitet och heuristiken har evaluerats genom en kvalitativ studie med 20 användare som har deltagit i interaktionen med vår prototyp.

Purpose – Artificial Intelligence has seen important growth in the digital area in recent years. Our aim is to explore possible guidelines that make use of AI advances to design good user experiences for digital products. Method – The proposed methods to gather the necessary qualitative data to support our claim involve open-ended interviews with UX/UI Designers working in the industry, in order to gain a deeper understanding of their thoughts and experiences. In addition, a literature review is conducted to identify the knowledge gap and build the base of our new theory. Findings – Our findings suggest a need to embrace new technological developments in favour of enhancing UX designers’ workflow. Additionally, basic AI and ML knowledge is needed to utilise these capabilities to their full potential. Indeed, a crucial area of impact where AI can augment a designer’s reach is personalization. Together with smart algorithms, designers may target their creations to specific user needs and demands. UX designers even have the opportunity for innovation as mundane tasks are automated by intelligent assistants, which broadens the possibility of acquiring further skills to enhance their work. One result, that is both innovative and unexpected, is the notion that AI and ML can augment a designer’s creativity by taking over mundane tasks, as well as, providing assistance with certain graphics and inputs. Implications – These results indicate that AI and ML may potentially impact the UX industry in a positive manner, as long as designers make use of the technology for the benefit of the user in true human-centred practice. Limitations – Nevertheless, our study presents its own unique limitations due to the scope and time frame of this dissertation, we are bound to the knowledge gathered from a small sample of professionals in Sweden. Presented guidelines are a suggestion based on our research and not a definitive workflow.