Meeting with PhD Advisor

Posted: August 28th, 2007 | No Comments »

Meeting to discuss my DEA thesis. We agreed that the focal point of my research shifted from uncertainty to granularity of location information. The first is a problem to solve (while sometimes being an opportunity), the latter is a source for interaction. In my model of the social-technical gap in location aware computing, I intend to define their relations. I hypothesize that uncertainty appears when a location system does not match the granularity of information expected by a user. So I keep the work I have done so far on the reactions (uncertainty) to fluctuating location information, and focus more on the factors influencing people to tune the information. This is what I need to further investigate in my ethno study of the taxi drivers (e.g. the funnel metaphor to access information, their use of neighborhoods, landmarks, addresses). Similarly with my Flickr study I could include the analysis of the textual description (i.e. tags) to understand how the users describe the granularity (for example: city -> landmark). Results of complete studies from different contexts could already be a nice outcome to define key aspect of human interaction with location information granularity in a mobile context. It could open the door to the definition of sub-issues (psycho, social, cultural, gender, …) that would be mostly outside of the scope of my thesis. No decisions have been made on further studies (let’s see what the outcomes of the 2 current studies), but we certainly don’t lack of ideas. The concept of granularity of location information is nothing new. However, it is worth revisiting it since “we use things that did not exist previously”.

As for the DEA thesis, he shared my mixed feelings. I believe I have not achieved a good breadth-depth ratio, trying to cover too many aspects of my research domain. Then I lacked of energy to argument the choice (why a mention to privacy? -> uncertainty as opportunity + studies in spatial cloaking) and linkage of the key concepts. However, I think the breadth of this initial scope will help me in the long run. We discussed that chapter 3 (literature review) was not well self-contained. That is that I did not argue enough for the choice of the topics, the perspectives I chose to cover them, and their relevance to my work. The last section (Discussion) clearly revealed that lack of connection between the concepts described and the future work. I should rewrite that part by focusing and arguing the key elements of my framework and their relations.

Relation to my thesis: Still not quite in the narrow part of the funnel… but working on it.

Visitors Interaction with a City

Posted: August 21st, 2007 | No Comments »

Ticket machines are often the first systems tourists must interact with when they arrive in a city. They are the first interface of the city. They give that first impression of how much a visitors is expected and welcomed. Yet, some cities still fail at providing decent interfaces for tourist to get around. The Norwegian newspaper published an article on the tourists struggle with local transport in Oslo. Contrary to the content of the article, the problem does necessarily come from the language, but also on the design of the overall system such as providing spatial clues (e.g. map) of the transportation network in space or matching the name of the main stations/stops with designations collected from the surrounding attractions.

Nicolas gave examples on the bad design of Lausanne ticket machines and the better tentative in Geneva.

Badtl Maptpg
Ticket machines in Lausanne (left), Geneva (right). Photos courtesy of Nicolas Nova.

Relation to my thesis: One of my current project deals with enhancing the tourist experience of the city. There is a lot to learn form the confusion of tourist interacting with current systems to use a city infrastructure. It could prevent producing similar errors in the design mobile location-aware application.

Methods for Social Computing

Posted: August 21st, 2007 | No Comments »

Karen Martin wrote a nice piece (with great images supporting the text) on Methods for Social Computing based on Paul Dourish’s Where the Action Is. Dourish defines “social computing,” as the attempt to incorporate sociological understandings into interface design. He grounds his argumentation on the idea of embodied interaction that is the notion that physical and social phenomena unfold in real time and real space as a part of the world in which we are situated, right alongside and around us. In consequence, Dourish argues, for the now more common approach of incorporating the understandings of how social practice emerges in the design of systems to fit more easily into the ways in which we work. Karen goes on defining the the methods to support social computing mainly ethnography, ethnomethodology (ethno with “practical sociological reasoning”, that is relying on people’s understanding/knowledge of their reasons for acting) and technomethodology (use of ethnomethodology not only for critique but also for design). The evaluation of the design should rely on similar contextualized methods out of the sterile confines of a laboratory. As Dourish concludes, “the only way to come to a good understanding of the effectiveness of a software system is to understand how it features as part and parcel of a set of working practices, as embodied by a group of people actually using the system to do real work in real working settings”. As Karen mentions, this critique remains at the core of discussion on the validity of HCI studies.

Relation to my thesis: Over the summer I read Andy Crabtree’s Designing Collaborative Systems : A Practical Guide to Ethnography that helped me setup my study of taxi drivers. It completes the more theoretical content of Where the Action Is.

An Extensive LBS Bibliography

Posted: August 21st, 2007 | No Comments »

Jonathan Raper uploaded an extensive bibliography of research in Location-Based Services (MobilityNewv2.txt) that mirrors the one in the Editorial Lead article of the upcoming first issue of the Journal of Location-Based Services.

Relation to my thesis: A complement to my current bibliography (in BibTeX).

Online Social Networking and Mobility Traces

Posted: August 20th, 2007 | No Comments »

As part of the Cityware Project in Bath, UK, Vassilis Kostakos released a Bluetooth application that links proximity data from the physical space (mobility traces) with the online network of Facebook. It aims at exploring how your real world and online social networks are intertwined. Whereas it has some similarities with Nathan Eagle’s Reality Mining, here the spatial traces are enhanced by the large amount of information disclosed on the web. The BBC has a piece on it: Bluetooth helps Facebook friends. The application is available at

Relation to my thesis: The linking of online social networking and mobility traces, goes in the same direction as what I have been working on with Flickr and what could be done with iFind.

Accepted: Paper at LBS2007

Posted: August 2nd, 2007 | 1 Comment »

The outcome of the work performed during this Spring’s stay at the MIT has been accepted for full presentation at the 4th International Symposium on LBS and Telecartography, November 8-10, 2007 in Hong Kong. The paper is entitled “Understanding of Tourist Dynamics from Explicitly Disclosed Location Information” by Fabien Girardin, Filippo Dal Fiore, Josep Blat, and Carlo Ratti

Abstract: In the recent years, the large deployment of mobile devices led to a massive increase in the volume of records of where people have been and when they were there. The analysis of the accumulated archives of such spatio-temporal data can derive high-level human behavior information valuable to urban planers, traffic engineers, and tourism authorities. In this paper, we describe our approach to analyze the history of physical presence of tourists from the digital footprints they publicly make available on the world-wide web. Our work takes context in the Province of Florence where besides data from survey-based hotel and museums frequentation, tourism authorities have limited information on the fluxes of visitors (i.e. previous and next destination) and on the nationalities of the tourists who do not sleep in town (i.e. excursionists). As a proof of concept, we used a corpus of 85910 publicly disclosed geotagged photos taken in the province by 3348 photographers over a period of 2 years. Based on the time, explicit location and people’s description of their photos, we design geovisualizations to reveal the tourist activity and flows in space and time. They provide insights on the density of tourists in the area the flow and activity of tourists within, in and on of that area.

Keywords: Spatio-temporal data analysis, geovisualization, location-disclosure, location-based services.

Relation to my thesis: Tracing the Visitor’s Eye is off to a good start. Plus now there is a shot to get the paper accepted in an upcoming book on Location-Based Services and Telecartography. Finally, this conf might be the opportunity to meet Jonathan Raper who will keynote.