Longitudinal studies have traditionally been seen as too cumbersome and labor-intensive to be of much use in research on Human-Computer Interaction (HCI). However, recent trends in market, legislation, and the research questions we address, have highlighted the importance of studying prolonged use, while technology itself has made longitudinal research more accessible to researchers across different application domains. Aimed as an educational resource for graduate students and researchers in HCI, this book brings together a collection of chapters, addressing theoretical and methodological considerations, and presenting case studies of longitudinal HCI research. Among others, the authors: discuss the theoretical underpinnings of longitudinal HCI research, such as when a longitudinal study is appropriate, what research questions can be addressed and what challenges are entailed in different longitudinal research designs reflect on methodological challenges in longitudinal data collection and analysis, such as how to maintain participant adherence and data reliability when employing the Experience Sampling Method in longitudinal settings, or how to cope with data collection fatigue and data safety in applications of autoethnography and autobiographical design, which may span from months to several years present a number of case studies covering different topics of longitudinal HCI research, from "slow technology", to self-tracking, to mid-air haptic feedback, and crowdsourcing.

Longitudinal studies have traditionally been seen as too cumbersome and labor-intensive to be of much use in research on Human-Computer Interaction (HCI). However, recent trends in market, legislation, and the research questions we address, have highlighted the importance of studying prolonged use, while technology itself has made longitudinal research more accessible to researchers across different application domains. Aimed as an educational resource for graduate students and researchers in HCI, this book brings together a collection of chapters, addressing theoretical and methodological considerations, and presenting case studies of longitudinal HCI research. Among others, the authors: discuss the theoretical underpinnings of longitudinal HCI research, such as when a longitudinal study is appropriate, what research questions can be addressed and what challenges are entailed in different longitudinal research designs reflect on methodological challenges in longitudinal data collection and analysis, such as how to maintain participant adherence and data reliability when employing the Experience Sampling Method in longitudinal settings, or how to cope with data collection fatigue and data safety in applications of autoethnography and autobiographical design, which may span from months to several years present a number of case studies covering different topics of longitudinal HCI research, from "slow technology", to self-tracking, to mid-air haptic feedback, and crowdsourcing.

This book constitutes the refereed proceedings of the 13th International Conference on Persuasive Technology, PERSUASIVE 2018, held in Waterloo, ON, Canada, in April 2018. The 21 revised full papers and 4 short papers presented were carefully reviewed and selected from 59 submissions. The papers demonstrate how persuasive technologies can help solve societal issues. They explore new frontiers for persuasive technology, such as personalized persuasion, new sensor usage, uses of big data, and new ways of creating engagement through gaming or social connection, focusing on a variety of technologies (e.g., web, wearables, AI, and smart environments). The papers are organized in the following topical sections: social means to persuasion; nudging and just-in-time interventions; design principles and practices; persuasive games; personalization and tailoring; and theoretical reflections.

Over the past decade the field of Human-Computer Interaction has evolved from the study of the usability of interactive products towards a more holistic understanding of how they may mediate desired human experiences. This book identifies the notion of diversity in users' experiences with interactive products and proposes methods and tools for modeling this along two levels: (a) interpersonal diversity in users' responses to early conceptual designs, and (b) the dynamics of users' experiences over time. The Repertory Grid Technique is proposed as an alternative to standardized psychometric scales for modeling interpersonal diversity in users' responses to early concepts in the design process, and new Multi-Dimensional Scaling procedures are introduced for modeling such complex quantitative data. iScale, a tool for the retrospective assessment of users' experiences over time is proposed as an alternative to longitudinal field studies, and a semi-automated technique for the analysis of the elicited experience narratives is introduced. Through these two methodological contributions, this book argues against averaging in the subjective evaluation of interactive products. It proposes the development of interactive tools that can assist designers in moving across multiple levels of abstraction of empirical data, as design-relevant knowledge might be found on all these levels. Foreword by Jean-Bernard Martens and Closing Note by Marc Hassenzahl.

Over the past decade the field of Human-Computer Interaction has evolved from the study of the usability of interactive products towards a more holistic understanding of how they may mediate desired human experiences. This book identifies the notion of diversity in users' experiences with interactive products and proposes methods and tools for modeling this along two levels: (a) interpersonal diversity in users' responses to early conceptual designs, and (b) the dynamics of users' experiences over time. The Repertory Grid Technique is proposed as an alternative to standardized psychometric scales for modeling interpersonal diversity in users' responses to early concepts in the design process, and new Multi-Dimensional Scaling procedures are introduced for modeling such complex quantitative data. iScale, a tool for the retrospective assessment of users' experiences over time is proposed as an alternative to longitudinal field studies, and a semi-automated technique for the analysis of the elicited experience narratives is introduced. Through these two methodological contributions, this book argues against averaging in the subjective evaluation of interactive products. It proposes the development of interactive tools that can assist designers in moving across multiple levels of abstraction of empirical data, as design-relevant knowledge might be found on all these levels. Foreword by Jean-Bernard Martens and Closing Note by Marc Hassenzahl.

This book constitutes the refereed proceedings of the 14th International Conference on Persuasive Technology, PERSUASIVE 2019, held in Limassol, Cyprus, in April 2019. The 29 full papers presented were carefully reviewed and selected from 79 submissions. The papers demonstrate how persuasive technologies can help solve societal issues. They were subsequently grouped in the following topical sections: Terminologies and methodologies; self-monitoring and reflection; systems development process; drones and automotives; ethical and legal aspects; special application domains; motivation and goal setting; personality, age and gender; social support; user types and tailoring.