A thesis submitted in 2009 by Fabien Girardin for the degree of Doctor of Philosophy in Computer Science and Digital Communication at the Universitat Pompeu Fabra, Barcelona, Spain.
ABSTRACT. The increasing use of mobile devices, wireless infrastructures, and the Internet is changing our daily lives, not only in the way we communicate with each other or share information but also how we relate to the environment. Through our interactions with these technologies we access and generate an informational membrane, hovering over the spaces we live in and visit. However, this information layer only imperfectly models the reality due to coarse digitization and technological limitations, challenging the human interaction. On the other hand, the presence of this user-generated ubiquitous geographic information opens novel perspectives in understanding human activities over space and time. This thesis takes on the challenge of exploring these aspects of human interactions with ubiquitous geographic information. Through qualitative and quantitative lenses, we discern the implications of the integration of ubiquitous geographic information and the resulting users strategies to cope with spatial uncertainty. Then, we exploit this contribution to explore novel approaches to infer individuals and groups time-space activities with respect to their privacy. We demonstrate the applicability of our solutions in the domains of market research and urbanism.
CHAPTERSRESEARCH BLOG. From March 2003, before my PhD coursework, to April 2009 I published in a research blog. It started as an attempt to move my research notebook online to forge new connections and keep track of my thoughts. This blog has proven indispensable as a research method used to communicate my work through about 1400 post and feedback from 400 comments. It became a research tool, part of general open science movement that not only regularly shared my research domain advances but also its hesitations and failures. This transparency on the implications of my work and the ones of my peers helped me cultivate a professional persona and build a reputation that allowed me to discuss my research work in continuation of conferences and also outside of the traditional academic venues. This informal network of researchers and professionals that belong to the readership of my blog represent an unvaluable goodwill that is part of the outcome of this thesis.