emerging world of real-time cellphone data, via the projects of the MIT SENSEeable City Lab. This lab has been producing interesting analysis and visualizations of cellphone data in urban centers, a.k.a. "digital footprints." We also spoke to Andrea Vaccari, a research associate at SENSEable City Lab, about a project as yet unpublished on their website. This project analyzed the economic impact from tourists, via cellphone data, of a huge art project the city of New York helped sponsor in 2008: four man-made waterfalls hosted around NYC from June to October.Last week we looked at the
From June 26 to October 13, 2008 there were four man-made waterfalls in New York Harbor. It was part art exhibit (conceived by the Danish/Icelandic artist, Olafur Eliasson) and part research project by MIT SENSEeable City Lab in collaboration with AT&T Research Labs. The project was commissioned by the Public Art Fund and was supported by the city of New York, which paid an estimated $20 million for it. The return was said to be about $69 million in total economic impact in New York City, due to tourists and other benefits of the waterfalls. Nearly 1.4 million people viewed The New York City Waterfalls from an official vantage point or from a ferry or tour boat between June 26 and October 13.
From a research point of view, the point of NYC Waterfalls was to map the distribution of visitors to the exhibit, and reveal where they took photos and communicated with their mobile phones. So the scope of this project was more than the previous research in cities such as Florence and Rome, where only the presence and movements of tourists was mapped. It's important to note too that only aggregate cellphone data was used - so no individually identifiable data was recorded.
This time the lab analyzed two types of digital footprints generated by people in proximity to the New York City Waterfalls: cellular network activity via AT&T and photo activity via Flickr publicly available photos.
There's a surprising amount of data about people that the lab can gather via Flickr. In 60% of the photos uploaded to Flickr that the lab studied, users had disclosed their nationality. This enabled the lab to infer whether they were citizens of New York or visitors, which is a valuable statistic to assess the economic impact of the waterfalls. Also the lab studied geographical coordinates, date and time, and other data Flickr revealed - e.g. description of the photo provided by the photographer. The Flickr API was used too.
From all of this, the lab was able to determine popular points of interest, and the chronologically ordered set of photos showed the movements of different individuals (again, note it was anonymized data).
What Can Be Gained From This Data?
The lab's findings were many. While the results may not be surprising (the waterfalls attracted more visitors!), what's important is that cellphone data provided quantifiable data about how much of an increase in activity the waterfalls generated. For example, the number of phone calls showed an increase of the "attractiveness" of waterfall vantage points by 39.1% in comparison to other points of interests in the vicinity - such as the WTC site, City Hall and Wall Street. This was based on historical cellphone data of the area, as well as the waterfall time period.
Not only did the waterfall vantage points gain in popularity, but other points of interest on the waterfront in the vicinity also improved - e.g. Main Street Park, Brooklyn Bridge and South Street Market.
Overall the analysis of digital footprints showed the impact of the waterfalls, and how they drove people to new parts of the city over time. MIT says that this type of information can feed tourism studies and help a city to understand the behavior of people (tourists) who can have a large impact on the local economy. This type of data would also be useful for urban planning, of future events and attractions.