Accessible On-Body Interaction for People With Visual Impairments

While mobile devices offer new opportunities to gain independence in everyday activities for people with disabilities, modern touchscreen-based interfaces can present accessibility challenges for low vision and blind users. Even with state-of-the-art screenreaders, it can be difficult or time-consuming to select specific items without visual feedback. The smooth surface of the touchscreen provides little tactile feedback compared to physical button-based phones. Furthermore, in a mobile context, hand-held devices present additional accessibility issues when both of the users’ hands are not available for interaction (e.g., on hand may be holding a cane or a dog leash). To improve mobile accessibility for people with visual impairments, I investigate on-body interaction, which employs the user’s own skin surface as the input space. On-body interaction may offer an alternative or complementary means of mobile interaction for people with visual impairments by enabling non-visual interaction with extra tactile and proprioceptive feedback compared to a touchscreen. In addition, on-body input may free users’ hands and offer efficient interaction as it can eliminate the need to pull out or hold the device. Despite this potential, little work has investigated the accessibility of on-body interaction for people with visual impairments. Thus, I begin by identifying needs and preferences of accessible on-body interaction. From there, I evaluate user performance in target acquisition and shape drawing tasks on the hand compared to on a touchscreen. Building on these studies, I focus on the design, implementation, and evaluation of an accessible on-body interaction system for visually impaired users. The contributions of this dissertation are: (1) identification of perceived advantages and limitations of on-body input compared to a touchscreen phone, (2) empirical evidence of the performance benefits of on-body input over touchscreen input in terms of speed and accuracy, (3) implementation and evaluation of an on-body gesture recognizer using finger- and wrist-mounted sensors, and (4) design implications for accessible non-visual on-body interaction for people with visual impairments

A sound idea: An investigation into accessible video game design for the deaf and hard of hearing

A widely accepted, and incorrect, assumption towards hearing accessibility in video games is that deaf and hard of hearing (DHH) users are those who encounter the least barriers and are generally well catered for. Rapid advancement in video game technology has seen video game sound evolve from simple blips generated by internal circuitry to fully realised digital audio used to convey critical information. To accommodate the DHH, this information needs to be conveyed in an alternative manner. However, evidence suggests existing accessible design solutions for the DHH lack specificity and are insufficient. Thus, the inability to hear, or hear well, has historically resulted in DHH users left with impeded experience and gameplay. This thesis describes an investigation to address the primary research question: How might accessible video game design practices be facilitated to better accommodate the deaf and hard of hearing? To examine this question, an action research method as part of a transformative mixed methods methodology was used. Data collection procedures included critical analysis of literature, observations, and a cross-sectional self-administered survey for triangulation. The critical analysis of literature exposed issues relating to accessible video game design, particularly in relation to the identification of solutions and technical implementation. Further, issues related to the classification of video game software were identified. This posed potential problems with identification of game design methods and led to the development of a new video game classification model. The new model informed an analysis on the methods used for the design of video games, and results were visually represented and mapped to the different approaches to accessible design. Subsequent analysis determined that a game assessment framework is a suitable approach to facilitating accessible design. Further investigation identified visual feedback as the most suitable form of complementary feedback to game audio. This led to the development of a new model to classify visual feedback elements used in video games, and identification of audio feedback categories based on diegetic film theory. Through triangulation of results, a new game feedback model (GFM) was developed. The GFM was used for observational experimentation to identify and classify individual visual feedback elements used in video games. Each element was analysed and mapped to categories of game sound. The resulting model, with populated data, was used to determine what visual feedback elements may be used to complement specific categories of critical game audio. A survey was subsequently used for triangulation, and resulted in amendments to the final model. Through iterative development, and interpretation of findings, the research culminated in the development of a game assessment framework. The three-step framework aids in the classification of game sounds; assesses the impact of those game sounds; and provides recommendations for complementary visual feedback elements for sounds identified as having an adverse impact on user experience and gameplay if they were to be removed. The framework is innovative and has the potential to provide practical guidance for developers of video games. In addition, this research provides the foundation for future research, with the potential to influence accessible game design for the DHH

Digital writing technologies in higher education : theory, research, and practice

This open access book serves as a comprehensive guide to digital writing technology, featuring contributions from over 20 renowned researchers from various disciplines around the world. The book is designed to provide a state-of-the-art synthesis of the developments in digital writing in higher education, making it an essential resource for anyone interested in this rapidly evolving field. In the first part of the book, the authors offer an overview of the impact that digitalization has had on writing, covering more than 25 key technological innovations and their implications for writing practices and pedagogical uses. Drawing on these chapters, the second part of the book explores the theoretical underpinnings of digital writing technology such as writing and learning, writing quality, formulation support, writing and thinking, and writing processes. The authors provide insightful analysis on the impact of these developments and offer valuable insights into the future of writing. Overall, this book provides a cohesive and consistent theoretical view of the new realities of digital writing, complementing existing literature on the digitalization of writing. It is an essential resource for scholars, educators, and practitioners interested in the intersection of technology and writing

Risks and potentials of graphical and gesture-based authentication for touchscreen mobile devices

While a few years ago, mobile phones were mainly used for making phone calls and texting short messages, the functionality of mobile devices has massively grown. We are surfing the web, sending emails and we are checking our bank accounts on the go. As a consequence, these internet-enabled devices store a lot of potentially sensitive data and require enhanced protection. We argue that authentication often represents the only countermeasure to protect mobile devices from unwanted access. Knowledge-based concepts (e.g., PIN) are the most used authentication schemes on mobile devices. They serve as the main protection barrier for many users and represent the fallback solution whenever alternative mechanisms fail (e.g., fingerprint recognition). This thesis focuses on the risks and potentials of gesture-based authentication concepts that particularly exploit the touch feature of mobile devices. The contribution of our work is threefold. Firstly, the problem space of mobile authentication is explored. Secondly, the design space is systematically evaluated utilizing interactive prototypes. Finally, we provide generalized insights into the impact of specific design factors and present recommendations for the design and the evaluation of graphical gesture-based authentication mechanisms. The problem space exploration is based on four research projects that reveal important real-world issues of gesture-based authentication on mobile devices. The first part focuses on authentication behavior in the wild and shows that the mobile context makes great demands on the usability of authentication concepts. The second part explores usability features of established concepts and indicates that gesture-based approaches have several benefits in the mobile context. The third part focuses on observability and presents a prediction model for the vulnerability of a given grid-based gesture. Finally, the fourth part investigates the predictability of user-selected gesture-based secrets. The design space exploration is based on a design-oriented research approach and presents several practical solutions to existing real-world problems. The novel authentication mechanisms are implemented into working prototypes and evaluated in the lab and the field. In the first part, we discuss smudge attacks and present alternative authentication concepts that are significantly more secure against such attacks. The second part focuses on observation attacks. We illustrate how relative touch gestures can support eyes-free authentication and how they can be utilized to make traditional PIN-entry secure against observation attacks. The third part addresses the problem of predictable gesture choice and presents two concepts which nudge users to select a more diverse set of gestures. Finally, the results of the basic research and the design-oriented applied research are combined to discuss the interconnection of design space and problem space. We contribute by outlining crucial requirements for mobile authentication mechanisms and present empirically proven objectives for future designs. In addition, we illustrate a systematic goal-oriented development process and provide recommendations for the evaluation of authentication on mobile devices.Während Mobiltelefone vor einigen Jahren noch fast ausschließlich zum Telefonieren und zum SMS schreiben genutzt wurden, sind die Anwendungsmöglichkeiten von Mobilgeräten in den letzten Jahren erheblich gewachsen. Wir surfen unterwegs im Netz, senden E-Mails und überprüfen Bankkonten. In der Folge speichern moderne internetfähigen Mobilgeräte eine Vielfalt potenziell sensibler Daten und erfordern einen erhöhten Schutz. In diesem Zusammenhang stellen Authentifizierungsmethoden häufig die einzige Möglichkeit dar, um Mobilgeräte vor ungewolltem Zugriff zu schützen. Wissensbasierte Konzepte (bspw. PIN) sind die meistgenutzten Authentifizierungssysteme auf Mobilgeräten. Sie stellen für viele Nutzer den einzigen Schutzmechanismus dar und dienen als Ersatzlösung, wenn alternative Systeme (bspw. Fingerabdruckerkennung) versagen. Diese Dissertation befasst sich mit den Risiken und Potenzialen gestenbasierter Konzepte, welche insbesondere die Touch-Funktion moderner Mobilgeräte ausschöpfen. Der wissenschaftliche Beitrag dieser Arbeit ist vielschichtig. Zum einen wird der Problemraum mobiler Authentifizierung erforscht. Zum anderen wird der Gestaltungsraum anhand interaktiver Prototypen systematisch evaluiert. Schließlich stellen wir generelle Einsichten bezüglich des Einflusses bestimmter Gestaltungsaspekte dar und geben Empfehlungen für die Gestaltung und Bewertung grafischer gestenbasierter Authentifizierungsmechanismen. Die Untersuchung des Problemraums basiert auf vier Forschungsprojekten, welche praktische Probleme gestenbasierter Authentifizierung offenbaren. Der erste Teil befasst sich mit dem Authentifizierungsverhalten im Alltag und zeigt, dass der mobile Kontext hohe Ansprüche an die Benutzerfreundlichkeit eines Authentifizierungssystems stellt. Der zweite Teil beschäftigt sich mit der Benutzerfreundlichkeit etablierter Methoden und deutet darauf hin, dass gestenbasierte Konzepte vor allem im mobilen Bereich besondere Vorzüge bieten. Im dritten Teil untersuchen wir die Beobachtbarkeit gestenbasierter Eingabe und präsentieren ein Vorhersagemodell, welches die Angreifbarkeit einer gegebenen rasterbasierten Geste abschätzt. Schließlich beschäftigen wir uns mit der Erratbarkeit nutzerselektierter Gesten. Die Untersuchung des Gestaltungsraums basiert auf einem gestaltungsorientierten Forschungsansatz, welcher zu mehreren praxisgerechte Lösungen führt. Die neuartigen Authentifizierungskonzepte werden als interaktive Prototypen umgesetzt und in Labor- und Feldversuchen evaluiert. Im ersten Teil diskutieren wir Fettfingerattacken ("smudge attacks") und präsentieren alternative Authentifizierungskonzepte, welche effektiv vor diesen Angriffen schützen. Der zweite Teil beschäftigt sich mit Angriffen durch Beobachtung und verdeutlicht wie relative Gesten dazu genutzt werden können, um blickfreie Authentifizierung zu gewährleisten oder um PIN-Eingaben vor Beobachtung zu schützen. Der dritte Teil beschäftigt sich mit dem Problem der vorhersehbaren Gestenwahl und präsentiert zwei Konzepte, welche Nutzer dazu bringen verschiedenartige Gesten zu wählen. Die Ergebnisse der Grundlagenforschung und der gestaltungsorientierten angewandten Forschung werden schließlich verknüpft, um die Verzahnung von Gestaltungsraum und Problemraum zu diskutieren. Wir präsentieren wichtige Anforderungen für mobile Authentifizierungsmechanismen und erläutern empirisch nachgewiesene Zielvorgaben für zukünftige Konzepte. Zusätzlich zeigen wir einen zielgerichteten Entwicklungsprozess auf, welcher bei der Entwicklung neuartiger Konzepte helfen wird und geben Empfehlungen für die Evaluation mobiler Authentifizierungsmethoden

Use of linguistic markers in the identification and analysis of chief executives’ hubris

This research seeks to provide an insight into the identification and understanding of linguistic markers of Chief Executive Officer (CEO) hubris. It analyses spoken and written discourse samples of CEOs deemed to be hubristic and benchmarks the results against those of a sample of non-hubristic CEOs. In doing so it explores the hypothesis that the linguistic utterances of hubristic CEOs show consistent differences from the language produced by CEOs who have not been identified as possessing hubristic tendencies. This thesis presents a review of academic literatures pertaining to personality, hubris and natural language use. The review of these three domains leads to the conclusion that certain personality traits are antecedents to hubris and can be identified in one’s language use. The word count strategies are reviewed in depth as a framework for measuring hubris at-a-distance through the assessment of CEO’s linguistic utterances. In addition to word count strategies, this thesis also proposes a new approach – applying machine learning techniques to the analysis of language - for identifying CEO hubris. The research consists of a Pilot Study and three main studies (Study 1, Study 2, Study 3 (comprising two sub-studies, 3a and 3b)). It describes in detail the process, methods and materials used, summarises findings and explains the implications of the results obtained for further research into linguistic markers of hubris. For the purpose of this research, Hubris Syndrome is conceptualised as proposed by Owen and Davidson (2009), including all 14 proposed symptoms for Hubris Syndrome (Owen & Davidson, 2009). This research focuses explicitly on leaders who occupy or have occupied the position of CEO for a significant amount of time and were identified by other researchers, subject matter experts and media as having exhibited the features of Hubris Syndrome during their time in office. This research proposes several innovative techniques to identify the differences between hubristic and non-hubristic language, and documents subtle differences identified. Findings from this doctoral study suggest that the high use of impersonal pronouns, the total count of pronouns, auxiliary verbs, common verbs and tentative tone indicate CEO hubris. All in all, exploring if and how hubris’ symptoms manifests in CEO language use and what are characteristic features of hubristic discourse, contributes to wider research regarding the diagnosis and prevention of this phenomenon. This study seeks to mitigate the risk of potentially destructive CEO behaviour for the organisation and prevent organisational failures induced or aggravated by Hubris Syndrome