A couple of paper that discuss the emergence of the large data generated by sensor now sharing our lives:

First, Data management in the worldwide sensor web draws the big picture in mentioning that now too much attention has been placed on the networking issues of distributed sensing and too little on tools to manage, analyze and understand the data. The authors ask the question weather we can design sensor networks with data quality in mind? They ask a very crucial question, but as often in location-aware computing, it is very unclear on who can claim what quality in location information is or in other words who can answer “how good is good enough?”. Of course it is important to manage temporal and spatial data and handle their inherent uncertainty (e.g. via probabilistic theory) or mask it (e.g. via interpolation) or play with it (seamful design). It seems clear now that my thesis is about acknowledging that situation (uncertainty in the location information, fluctuant quality in the data), but instead of aiming to produce “perfect data”, I plan to provide an understanding and solutions from a human and urban perspective. It comes, at the first place, with the observation of people experiencing location-aware systems in CatchBob!, and making use of location information, in my taxi driver (co-evolution, context and granularity). This observations help me accumulating evidences on the contextual factors influencing the granularity (≈human expectation of quality) of the location information used.
Balazinska, M., Deshpande, A., Franklin, M. J., Gibbons, P. B., Gray, J., Hansen, M., Liebhold, M., Nath, S., Szalay, A., and Tao, V. (2007). Data management in the worldwide sensor web. IEEE Pervasive Computing, 6(2):30–40.

Second, Citizens as Voluntary Sensors: Spatial Data Infrastructure in the World of Web 2.0 discusses that the most powerful sensor web is made of the 6 billion humans occupying Earth’s surface. This large collection of mobile and intelligent sensors will affect the processes by which geographic information acquisition and compilation (VGI: volunteered geographic information). The data generated suffer similar issues as a top down (authoritarian, centrist paradigm) when it comes to the fluctuating quality in the data and trust. However, the notion that citizens with means of taking measurements is at the source of the solution to the problems mentioned above. The analysis of how these “citizens” handle and annotate their measurements and observations allow to further understand the influencing factors in the use of location granularity. This is why I study Flickr users in their spatial annotation practice and in their use of geographic semantics.
Goodchild, M. F. (2007). Citizens as voluntary sensors: Spatial data infrastructure in the world of web 2.0. International Journal of Spatial Data Infrastructures Research, 2:24–32.

Third, the digital traces (shared measurements/observations) left by people in space allow to define a human description of space (e.g. citizen definition of a neighborhood). This type of sensor web data can only make sense with geovisualization, as the ones presented in Interactive Visual Exploration of a Large Spatio-temporal Dataset: Reflections on a Geovisualization Mashup. The authors explore the new opportunities for visualizing sensor web data to explain user behaviors. Tools such as Google Earth provide a quick support for visual synthesis and preliminary investigation of digital traces.
Wood, J., Dykes, J., Slingsby, A., and Clarke, K. (2007). Interactive visual exploration of a large spatio-temporal dataset: Reflections on a geovisualization mashup. IEEE Transactions on Visualization and Computer Graphics, 13(6):1176–1183.

Relation to my thesis: Each of these three paper give an overview of the main themes of my thesis that aims to take a human and urban perspective to define the quality of location information:
1. Issues in the quality in the location data (uncertainty).
2. New data to observe people handle/experience location granularity in order to collecting evidences.
3. New visualization to reveal how people perceive and describe the urban space

In Denis Wood’s Cartography is Dead (Thank God!)

I have no interest in belittling the positive contributions made by the generations of academic cartographers - but there’s a lot that was dead wood to begin with, and is so rotten today it’s threatening the rest of it. All the prescriptive bullshit, every map must have a legend and a scale - all that - ignored in fact on a gazillion effective, useful maps, all that has to stop. And design! Academic cartographers have never understood a thing - not a thing -about design. God knows that, as a group, the least interesting, least attractive, least significant maps have been made by university cartographers: all that design talk, from design illiterates, that’s got to stop.

Relation to my thesis: A new type of science of mapmaking (or communication through maps) will need to take into account geo-communication mechanisms (as suggested by Lars Brodersen) and an understanding of the user and its context to inform the design. It will also need to inspire and communicate with the artists, engineers, designers, urban planners, … sociologists, ethnographers, psychologists, visionary, … astronomers, “canal diggers” who inspire compelling and significant work such as Kevin Lynch’s “mental maps” of Boston or Joseph Minard’s Napolean March.

Late last year, a position paper I submitted to the Urban Mixed Reality workshop at CHI’08 was only accepted as a poster presentation. In this paper, we propose that digital footprints present an opportunity to the residents and tourists the ability to look down on the city and view the activities and their consequences. When this information is fed back to the community, it can inform the decision-making and change the behaviors through social navigation. However, the design of a social navigation service should take into consideration the lack of accuracy in space and time of digital footprints. Apparently, the unique reviewer who rejected the paper understood that we propose the use of digital footprints to support people in navigating (orientation/path/aims) in the city.

So I thought that instead of flying overseas to present a poster, it might be more relevant to leave this position paper online with its reviews, open for discussion and thoughts to the reader of this blog. Considering the encouraging comments of the second reviewer, I will most probably recycle it for future publications.

Leveraging urban digital footprints with social navigation and seamful design
Girardin, F., Nova, N., Dal Fiore, F., Ratti, C., Blat, J.

Abstract. The widespread deployment of mobile and wireless technologies increases the amount of recorded interactions between humans and the urban environment. The accumulation of these digital footprints provides new opportunities to reveal human behaviors in space. Beyond their utility to improve the quantity and quality of mobility data already available to urban planners and local authorities, this information can be returned to residents and visitors to enhance their perception of the space and inform their discussions and decision making. In this paper, we argue that digital footprints, when properly revealed, can act as social navigation cues to support the exploration of the city.

[Full paper - 104KB]

Reviewer 1 (reject):
The paper discussed ideas on how to make patterns of mobility and flow based on digital footprints available to tourists and residents. The discussion is based on two concepts – ‘social navigation’ and ‘seamful design’. I miss a reflection on previous studies on supporting people’s orientations/paths/aims when moving in a city through giving them visual information. This is a quite complex endeavor and it is not sufficient to provide a ‘vision’ without thorough grounding. For example, I don’t underdstand the usefulness of ‘seams’ (uncertainty of data, lack of timeliness, etc.) for people. You may want to read Bill Gaver’s paper on ‘Ambiguity as a resource for design’.

Reviewer 2 (accept):
The paper argues for the use of digital footprints as social navigation cues for the exploration of the city. Digital footprints are space and time referenced data that are produced by the increased amount of recorded interactions between humans and the urban environment. The paper presents an approach meant to leverage this kind of mobility data to support awareness of the overall dynamics of an urban space and affect the discussion and decision-making of residents and visitors in that space. Challenges inherent to the rendering of spatio-temporal data in mobile and urban environments are addressed by adopting a “seamful design” approach revealing the imperfection of the sensed data.

The contribution of the paper to an overall framework for the social use of mobility data is timely and likely to raise discussion. Suggestions for improvement: the authors may want to better explain the idea of “cultural views of mobility” and provide more examples on the kind of data that could be used and how their visualization would inform people’s behaviour in the urban space.

Urban Mapping, a provider of geospatial data and services released today an API to access its Urbanware Neighborhood database and computation logic for neighborhoods, other informally-defined regions and transit systems. This service include neighborhoods located at a point/location, neighborhoods within a city or bounding box, alternative neighborhood names, relationships with other neighborhoods (nesting, aliases, dominance), multi-lingual support, intersecting postal codes and intersecting municipalities.

Relation to my thesis: Human’s perspective of the space hardly translates to its digital definition stored geographic information systems (see Defining Neighborhoods and User-Centered Approach on Geodata). I am eager to play around with the Urbanware API (the dataset includes Barcelona)

While finishing a journal paper on our initial results of Tracing the Visitor’s Eye, I completed the development of my “Urban Dynamics” software to visualize on top of Google Earth the tourist density and flows. There is an explanatory page with examples of Barcelona, Spain and Florence, Italy available in: 3D geospatial visualization of tourist density and flows

Relation to my thesis: I have been developing “Urban Dynamics” as a tool to analyze spatio-temporal data of field studies. It is also a piece of work that proves that 2008 might be the year of Neogeographer as suggested by Andrew Hudson-Smith at CASA.

People at the Chronos Group digged up the term “chronotope” from the 90s. According to Wikipedia, chronotope can be literally translated as “time-space”. In the context of urbanism, it highlights the temporal features of the city (see Une interprétation chronotopique by Alain Guez). The increasing availability of digital traces allows new perspectives of chronotopic analysis of urban spaces. The chronotopic visualizations (and tools) developed in WikiCity and Tracing the Visitor’s Eye most definitively go in the direction of revealing the “mobilities” not only in space but also over time (history and real time).

A few events I would love to attend in early 2008, but I unfortunately won’t be able to…

The Mobile City conference
Is it still useful or even possible to talk about the city as being only physical? Or about the digital world as purely ‘virtual’ (in the sense of ‘not real’ oimmaterial)? The physical city and the spaces of digital technologies merge into a new “hybrid space”. Hybrid spaces are shaped by the social processes that concurrently take place in digital and physical spaces. What is the influence of these developments on the ideas we have of time, space and place, citizenship and identity?

4th and 5th seminars in the ESRC Research Seminar Series: Rethinking the Urban Experience: the Sensory Production of Place
Seminar on the sensory awareness of urban infrastructure. This seminar will ask questions about the infrastructure that supports urban society. Topics may include sensory experiences of public transport networks, olfactory responses to waste and its disposal, public toilet provision in urban areas. Additionally, the role of hidden infrastructures such as CCTV and underground infrastructures such as utilities networks will be considered in this seminar.

EPFL Choros group “Penser l’espace” seminar with a focus on the “critique de la raison cartographique” and the multiple perspectives to think about space.
Quelles habitudes de pensée sont charriées lorsqu’on cartographie ? Quelles sont les implications de la réduction cartographique de la complexité de l’espace ? De quelle façon peut-on contrôler le passage des données à la carte ou le passage de la pensée à la carte ? Comment cartographier de l’espace contemporain – ce « space of flows » et hyperurbanisé - où la mobilité et la digitalité sont les caractéristiques fondamentales ? Quelles sont les implications du passage de la carte sur papier à la carte sur écran ? Le GPS et Google Earth transforment-ils notre rapport à la carte, et, partant, notre rapport à l’espace ?

Pervasive Persuasive Technology and Environmental Sustainability workshop at Pervasive 2008
The key theme of this workshop around environmental sustainability will be addressed threefold: 1. Providing people with environmental data and educational information, 2. Pervasiveness can easily turn invasive. It has already caused negative consequences in biological settings. 3. digital divide between humans and the environment (e.g. Can the process of ‘blogging sensor data’ (sensorbase.org) assist us in becoming more aware of the needs of nature? How can we avoid the downsides?

Inaugural Research Institute for the Science of Socio-Technical Systems
A science of socio-technical systems is emerging from research in the fields of HCI, social computing, social informatics, CSCW, sociology of computing, and other domains. The Consortium for the Science of Socio-Technical Systems (CSST) is a new organization devoted to advancing research on socio-technical systems. A primary goal of the institute is to build a new cohort of faculty and graduate students who are interested in research on the design and interplay of technology and humans at the level of individuals, groups, organizations, and larger communities.

ifgi Spring School 2008
Two weeks of short block courses with innovative topics in GI such as: geospatio-temporal information: issues in representation and reasoning, usability and user-centred systems, location-aware systems, information visualization & presentation, and research methods

I have been on the field collecting more observations and interviews on the adoption of GPS by taxi drivers in Barcelona. On one hand I am interested in the co-evolution process and the modifications of the practices, on the other hand I focus on the context of use of the technology (other artifacts/tools, influence of landmarks, type of location information used (how, where, when, granularity). Here are a few notes that will need to be interpreted further. I collected data from a unbalance population of either find very experienced (15+ years: seniors) taxi drivers or novice in the practice (2- years: juniors). It has been harder to anybody in between. At least, it revealed dissimulates in the appropriation of the technology between the “seniors” and “juniors”.

Uniformity in the wild
First of all, there is a concenus that GPS an unbeatable tool when it come to reaching a specific destination in a village and leaving it (link to previous post). It is a strong reason to acquire a sat-nav system. But it is not really to be more productive and hence earn more, rather than feeling more serene (i.e. tranquility was the word). Some mention that it does not only tranquilize them but also their clients (”they know I cannot cheat them with it”, “it reassures them that I go to the proper destination”). When it comes to seniors, they now know that they have a “companion” (some refereed to their car with an affectionate “she” and their sat-nav with a “he”) can take them anywhere and avoid these moment when they had to search endlessly browsing the street directories of the suburbs of Barcelona, asking their colleagues via radio or mobile phone. One mentioned me that “the fear of getting lost with a client I felt in my stomach now disappeared”. Another was relieved that he did not have to use his radio to ask colleagues about particular location informations and wayfinding (even though many taxi drivers are extreme social animals). Currently the radio is uniquely used to get dispatching orders and professional questions (e.g. asking on special rates for some destinations). To get out of the unfamiliar environment, the driver would be either very cautious in the path taken to enter the area (”I am a very good observer”) or use their GPS with destination Barcelona. In their exit strategy, their reach their bookmark of saved destinations are hit “home”, “Barcelona, any street”, or “Barcelona center”.

Disparities in the urban space
However, when it comes to the context of the city, practices differ and the “Guia” comes into play. The “Guia” is a dense book of all the streets and POI in Barcelona. Experienced drivers have been using it all their professional lives and have partially learned the city with it. Another big part of the knowledge drivers acquire come from the clients themselves. They know all the tricks and secrets official books and commercial systems can’t tell. As the experience drivers contain most of the knowledge of the city in memory they rarely return to the Guia. In fact, they prefer using their sat-nav and hit the Guia only as fail-over (e.g. when the system does not contain a street number or lacks of information). Even after 20 years of experience, one drivers still perceived accessing the Guia as a demanding task. Compare to that, hitting the screen of his Tom-Tom was a pure pleasure. This process of accessing correct information is executed differently by the juniors I interviewed. First, they had mixed feelings about their experience with their GPS (”It is like my mobile phone, sometimes it does not work well”, “it is a potential problem”) in terms of quality of services and precision of the information. They very early reached the limits of the systems and the inaccuracy (erroneous information) of the system directly impacted the quality of their service (mostly because they had to deeply rely on it in the beginning). In consequence, they embraced the use of the “Guia” which is “more accurate and complete” (particularly when it comes to POI). In the city, they learned not to completely rely on their sat-nav (because it is hard for them to judge if the information is erroneous or not) and first open the “Guia” prior to enter an address. One told me that he learned to interpret the system and its errors. When a conflict emerges between his sat-nav and his “knowledge” he starts to “improvise” (in his own terms). Depending on the circumstances he would either switch it off or ignore it for a while.

The confirmation of the funnel
Confirming what I mentioned previously, the wayfinding practice takes place in 2 main stages. There is a separation difference between “ir” (to go) and “llegar” (to arrive) and the location information are different in each phase. First the driver has the knowledge of the area where to go or checks in the Guia to get a rough awareness of destination (one driver told me he would directly enter the address in his navigation system). This is done at any occasion at a traffic light or in dense traffic (if the driver knows he will have to go on the highway directly, he/she will check prior to leaving). It is only at the entrance of the area (e.g. a neighborood - it would be interesting to define it better) that the active mode of the sat-nav system starts by entering the full address (once again taking advantages of traffic lights and busy traffic).
Mobile phone
The mobile phone often available is seen as a social link to family and friends, and is very rarely used as a tool to support their work. One driver told me that he used it a few times to check if a table was available at a restaurant for clients (particularly foreigners). This is a service he gives as added value, but he “normally should not do it”.

Passive mode
As mentioned in a paper by Nick Forbes,there is a clear tendency to keep the system in passive mode at any time. It is done so mainly to keep track of the radars (seems to be more a priority for experienced drivers) and (for juniors) to keep an awareness of where they are (keep track of the proximate streets) and it was also very valuable to learn the city. On this point, an experienced driver explained me that younger drivers who use a navigation system do not gain knowledge of the city, because they follow the recommendations and “stop to think”. My contact with the younger generation proved somehow the opposite. They are eager to learn the city and the imperfection of their systems forced them to get knowledge from the “Guia” and from the clients.

Relation to my thesis: Working on The co-evolution of taxi drivers and their in-car navigation systems, I stereotyped a bit the practices based on my notes to reveal the main patterns. I keep 3 main tracks that are worth investigate more in details:
- different appropriation of the location-aware system depending on the overall knowledge and experience of the space. The shortcoming of GPS forced the younger generation to rely on the Guia, while the older generation has little use of the Guia now. This goes in the direction of understanding and supporting “mobilities” instead of mobility.
- a tool not to make more money, nor to improve the efficacy, but to tranquilize (”I can go everywhere”) and relax (e.g. passive mode to have a continuous awareness)
- funnel-type of access to location information (I will model the process, this is part of the understanding of granularity) with multiple sources (kwnoledge, sat-nav and Guia)

Last Friday, at the Salon ImmoTICs DomoTICs Agora in Sophia Antipolis, France, I was very fortunate to present some of my work in a slot between the french “paleanthropologist” Pascal Picq and the italian architect David Fisher and later the economist/thinker Michel Godet. My talk (in french) entitled “Révéler le pouls de la ville” was a duplicate of what I presented at Mobile Monday Barcelona, with a stronger emphasis on the implications of the use of “digital footprints” by urban planners, local authorities and designer of urban digital infrastructures such as location-based services. The slide are available online: Révéler le pouls de la ville.

Thanks to Dominique Thibault for the kind invitation.

Relation to my thesis: testing my ideas + practicing public speaking (it is definitively either in my mother tongue) + getting in touch with french academics who do not always communicate outside of the boundaries of the “hexagone”.

Last night, I participated to the Mobile Monday Barcelona event on Location-Based Services. My talk entitled “Mapping of City Dynamics” covered some innovative ways to use mobile and wireless technologies to sense the city and reveal its pulse (i.e. its activity in space and time). I also discussed their underlying concepts (real-time, history, feedback loop, implicit and explicit acts, experience of the city, consequences of our activities) and their implications in relation to the design of location-based services that raise. Finally, I exemplified these ideas by introducing the ongoing project lead at the SENSEable City lab, named WikiCity, that aims at offering an instrument for city inhabitants to base their actions and decisions upon in a better informed manner.

Thanks to Rudy and Carles for the invitation! (Flickr set of the event)

The slides with my notes are available: Mapping of city dynamics

Relation to my thesis: Pushing the ideas on urban computing and the design of LBS (granularity, areas of influence/relevance, uncertainty) and getting good contacts to understand the partitioners perspectives. and past experiences. I will do a similar talk on Friday at the ImmoTICs DomoTICs Agora event in Sophia Antipolis.