Very interesting article. Thanks for sending it us Udhay. Wouldn't this also raise other kinds of security issues like for example, given that the hotspots of a city are now available, would terrorists also have access to it while planning a strike to maximize damage? How would they deter the use of CitySense for those kinds of negative purposes?
Raja. On Mon, Mar 16, 2009 at 9:40 AM, Udhay Shankar N <ud...@pobox.com> wrote: > This is rather cool, though there are obvious implications for privacy > here. > > Two things come to mind: > > * The "mapping a city using the sound of footsteps" bit from > _Cryptonomicon_ > * This is "traffic analysis" in more than one sense. :-) > > Udhay > > http://www.technologyreview.com/communications/22286/?a=f > > Friday, March 13, 2009 > > Mapping a City's Rhythm > A phone application highlights hot spots and will soon show where > different urban "tribes" gather. > > By Kate Greene > > Over the course of any day, people congregate around different parts of > a city. In the morning hours, workers commute downtown, while at > lunchtime and in the evening, people disperse to eateries and bars. > > While this sort of behavior is common knowledge, it hasn't been visible > to the average person. Sense Networks, a startup based in New York, is > now trying to bring this side of a city to life. Using cell-phone and > taxi GPS data, the startup's software produces a heat map that shows > activity at hot spots across a city. Currently, the service, called > Citysense, only works in San Francisco, but it will launch in New York > in the next few months. > > On Wednesday, at the O'Reilly Emerging Technologies conference in San > Jose, CA, Tony Jebara, chief scientist for Sense Networks and a > professor at Columbia University, detailed plans of a forthcoming update > to Citysense that shows not only where people are gathering in real > time, but where people with similar behavioral patterns--students, > tourists, or businesspeople, for instance--are congregating. A user > downloads Citysense to her phone to view the map and can choose whether > or not to allow the application to track her own location. > > The idea, says Jebara, is that a person could travel to a new city, > launch Citysense on her phone, and instantly get a feel for which > neighborhoods she might want to spend the evening visiting. This > information could also help her filter restaurant or bar suggestions > from online recommendation services like Yelp. Equally important, from > the company's business perspective, advertisers would have a better idea > of where and when to advertise to certain groups of people. > > Citysense, which has access to four million GPS sensors, currently > offers simple statistics about a city, says Jebara. It shows, for > instance, whether the overall activity in the city is above or below > normal (Sense Networks' GPS data indicates that activity in San > Francisco is down 34 percent since October) or whether a particular part > of town has more or less activity than usual. But the next version of > the software, due out in a couple of months, will help users dig more > deeply into this data. It will reveal the movement of people with > certain behavior patterns. > > "It's like Facebook, but without the self-reporting," Jebara says, > meaning that a user doesn't need to actively update her profile. "We > want an honest social network where you're connected to someone because > you colocate." > > In other words, if you live in San Francisco and go to Starbucks at 4 > P.M. a couple of times a week, you probably have some similarities with > someone in New York who also visits Starbucks at around the same time. > Knowing where a person in New York goes to dinner on a Friday night > could help a visitor to the city make a better restaurant choice, Jebara > says. > > As smart phones with GPS sensors become more popular, companies and > researchers have clamored to make sense of all the data that this can > reveal. Sense Networks is a part of a research trend known as reality > mining, pioneered by Alex Pentland of MIT, who is a cofounder of Sense > Networks. Another example of reality mining is a research project at > Intel that uses cell phones to determine whether a person is the hub of > a social network or at the periphery, based on her tone of voice and the > amount of time she talks. > > Jebara is aware that the idea of tracking people's movements makes some > people uncomfortable, but he insists that the data used is stripped of > all identifying information. In addition, anyone who uses Citysense must > first agree to let the system log her position. A user can also, at any > time, delete her data from the Sense Networks database, Jebara says. > > Part of Sense Networks' business plan involves providing GPS data about > city activity to advertisers, Jebara says. But again, this does not mean > revealing an individual's whereabouts--just where certain types of > people congregate and when. For instance, Sense Networks' data-analysis > algorithms may show that a particular demographic heads to bars downtown > between 6 and 9 P.M. on weekdays. Advertisers could then tailor ads on a > billboard screen to that specific crowd. > > So far, Jebara says, Sense Networks has categorized 20 types, or > "tribes," of people in cities, including "young and edgy," "business > traveler," "weekend mole," and "homebody." These tribes are determined > using three types of data: a person's "flow," or movements around a > city; publicly available data concerning the company addresses in a > city; and demographic data collected by the U.S. Census Bureau. If a > person spends the evening in a certain neighborhood, it's more likely > that she lives in that neighborhood and shares some of its demographic > traits. > > By analyzing these types of data, engineers at Sense Networks can > determine the probability that a user will visit a certain type of > location, like a coffee shop, at any time. Within a couple of weeks, > says Jebara, the matrix provides a reliable probability of the type of > place--not the exact place or location--that a person will be at any > given hour in a week. The probability is constantly updated, but in > general, says Jebara, most people's behavior does not vary dramatically > from day to day. > > Sense Networks is exploring what GPS data can reveal about behavior, > says Eric Paulos, a professor of computer science at Carnegie Mellon. > "It's interesting to see things like this, [something] that was just > research a few years ago, coming to the market," he adds. Paulos says it > will be important to make sure that people are aware of what data is > being used and how, but he predicts that more and more companies are > going to find ways to make use of the digital bread crumbs we leave > behind. "It's going to happen," he says. > > > -- > ((Udhay Shankar N)) ((udhay @ pobox.com)) ((www.digeratus.com)) > >