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MIT Researches Map Cell Phone Usage

Posted by Zonk on from the take-a-look-at-hookup-hill dept.

stlhawkeye writes "MIT researchers with the Mobile Landscape Projects have mapped a city based on cell phone usage. The article includes a map of Graz, Austria with a color-coded overlay indicating cell phone usage in various parts of the city. Using call origin and destination data, they are able to not only reverse-engineer a topographic map of the geography and landscape, but one of phone usage as well. The implications of the research have practical applications in law enforcement, emergency management, and traffic management. There are also, of course, privacy implications."

15 of 88 comments (clear)

  1. Reception... by TheOtherAgentM · · Score: 4, Insightful

    Maybe this can be used to carriers a general idea of where there reception is good and bad. Maybe then they'll believe me when I complain that they need more antennas.

    1. Re:Reception... by Pembers · · Score: 2, Insightful

      The phone company has to keep records about where each call originated so that they can bill you properly. The network automatically keeps aggregate statistics about what's happened in each cell - how many times someone tried to make a call, how many calls connected, how many calls completed successfully, how many were cut off because of signal loss, that sort of thing.

      If they see a high rate of failure coming from one cell, they can tell the network to gather more detailed information about it for a while. The reason they don't do this automatically is because the data can add up to gigabytes per cell per day, and nearly all of it's useless. The difficulty isn't in parsing the data - I do that for a living - but in storing and analysing it quickly enough that the results aren't so old as to be irrelevant.

      Fixing problems of signal strength or quality can be just a matter of reorienting an antenna by a few degrees, but putting up a new tower in an area that already has one is not a trivial task. The kit is expensive, and they cost a lot to run. Most companies would want to be reasonably sure that the new tower will pay for itself. Then they have to find somewhere to put it. Then they have to persuade whoever owns the land or the building to let them put it there. Then they have to argue the case with the local authorities. Then they have to win over residents who think the tower will give them cancer and lower their property values...

      --

      Just another wannabe fantasy novelist...

    2. Re:Reception... by stupid_is · · Score: 2, Insightful
      yup

      My telco (Orange in UK) refunds the cost of dropped calls, so if I'm wandering around and the call drops, I don't get charged. Also, when you turn your phone off, some signalling goes up to the network to tell them that.

      One thing no-one has touched on is that the operator also has the regulatory considerations to their coverage - they may be required to cover a certain square mileage / proportion of the population (certainly in 3G) which means that they may have to cover an area entirely populated with Luddites with no cell-phones. As you may guess, this gets quite expensive in hardware, so the radio planning is tweaked to the extreme to stretch coverage as far as possible in some places.

      (Note - I work on 3G, which the above applies to. I don't know how much regulation is present in 2G licenses. I wasn't that impressed with the article though - it seems they've just put a fancier GUI to present information that an operator would already collect)

      --
      -- Intelligence is soluble in alcohol
  2. Re:Geography... by MrAnnoyanceToYou · · Score: 1, Insightful

    Austrian girls are occasionally incredibly smoking hot, FYI. Two or three of the most beautiful women I've ever met were Austrian.

    --
    My little site.
  3. Good demographic info, too by Anonymous Coward · · Score: 3, Insightful

    In the figure in the original link, the big peak at the right rear is the location of the technical university. So, it shows that college students use cell phones heavily, which could never have been discovered otherwise. ; )>

  4. Privacy implications? by sploxx · · Score: 5, Insightful

    What are the privacy implications if the study only uses anonymized location data, i.e. "in this field of 100m x 100m", there is a cell phone which now moves to this field etc.?

    I think there are none. At least not any new ones than those implications by using cell phones at all.
    The data about who uses which cell when does exist already and it needs to exist, in the current state, at all times in the phone system (how would you route calls without this information?)

    Privacy concerns can surely be raised about storing such tracking profiles attached to particular persons. But just anonymized usage patterns?

  5. Considerable by Ungrounded+Lightning · · Score: 2, Insightful

    What are the privacy implications if the study only uses anonymized location data, i.e. "in this field of 100m x 100m", there is a cell phone which now moves to this field etc.?

    There are considerable privacy implications.

    For example: Law enforcement might notice cellphone activity in an area where none is expected - and go see what's going on there. Result: The uncover SOMEthing (a rave, a tresspass, a hermit, a criminal enterpirse, a fugitive, a meeting of political dissenters, ...) and initiate action - like a search to find out more.

    Search without probable cause. Tainted.

    Search based on telephone call traffic analysis. (In the US, at least, law enforcement is NOT supposed to have any call connection information unless they have obtained it pursuant to a limited-time authorization which must be obtained only when there is probable cause to believe a crime is committed BEFORE the information is released to the police.

    Annoyance - or even busting - of innocents. (I.e. somebody out camping uses his cellphone a lot - like he's verbose or is reading email - and the cops are looking for drug farmers in that park and come by to search his campsite. And perhaps looking bad because they've now done this twenty times without finding anything and/or because the guy "looks guilty" they decide to plant something on him. Or the poor sap happened to set up camp twenty feet from a pot grower's garden...)

    The very existance of that map may be an invasion of the privacy of the cellphone users in the area.

    Another poster asked: "What the hell are MIT researchers doing at Austria?!?" Perhaps they were there because they couldn't get the data HERE due to our privacy laws.

    --
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    1. Re:Considerable by BrokenHalo · · Score: 2, Insightful
      Perhaps they were there because they couldn't get the data HERE due to our privacy laws.

      If the "here" to which you refer is America, I would probably take Austria's privacy laws over yours, if given the choice. Given how the US administration is taking the so-called "war on terror" hype as such an excellent excuse to cancel any right to privacy, I'm not sure the US is a place I'd want to be. Of course, it doesn't help that other governments (e.g. Australia, Britain) are gleefully following suit...

    2. Re:Considerable by Kadin2048 · · Score: 3, Insightful

      I think that your conclusion -- that there might be some significant privacy applications here -- is correct, but your examples are weak.

      I see no reason why aggregate, anonymized call origination data couldn't be used by police. In particular the example about police noticing an inordinate amount of calls from a location where there normally aren't any. I don't see any privacy violation in this.

      Imagine that instead of looking for cell phone calls, which are electromagnetic waves being blasted into the ether, the cops were looking for visible light. They drive by a big abandoned farmhouse and notice lots of lights on. This doesn't give them probable cause to search, but it does give them a reason to knock on the door and ask for permission to search. And if, like many abandoned buildings, the property owner has previously informed the police that the building is posted against trespassing and unoccupied, they may be within their rights to walk right in unannounced, depending on the local laws.

      This is no different from the cell phone case. Only in one situation they're seeing visible light, in the other it's electromagnetic radiation produced by two-way radios (that's what your cell phone is, after all). They can't enter and search a house based ONLY on this, obviously, just like they couldn't if it was just light emanating from the building. If they then went to investigate though, and found probable cause, or were given permission to search, any resulting arrests would not be "tainted."

      The only way the privacy violation would come into play would be if the police, without a warrant or wiretap order, used the unique identification number of your phone plus the network's location data to put you at a certain location at a certain time. That, I think, would be obviously inadmissible, unless the records were kept by the carrier as a matter of course and obtained by a legitimate subpoena after the fact.

      The difference, imo, is when an individual is being singled out for close observation and monitoring, versus when the data is being used anonymously and in aggregate. To come back to the original example of the rave/clandestine meeting/meth lab in the abandoned building, if the police saw that suddently there were 20 active cellphones where for the last year there have been zero, and decided to drive by and check it out, that's perfectly fine. But if they come and arrest you for trespassing because YOUR cellphone was operating from within said property at 2:43 AM last night, when there wasn't a warrant or wiretap order from a judge outstanding already, that's clearly not.

      I am, of course, a nobody, so there's no reason my opinion counts for anything. However based on previous rulings concerning things like infrared observation from aircraft (to look for buildings that are being used as industrial marijuana growing operations), I wouldn't be surprised if what I just outlined is how things eventually work out.

      --
      "Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
    3. Re:Considerable by gumbi+west · · Score: 2, Insightful
      Sorry, so you think that you should be able to carry around a radio transmitter, on and broadcasting, and the other people shoulnd't be able to look for it?

      Where is the reasonable expectation of privacy? The only way I see reasonable expectation of privacy is if a law is specifically passed that says that you have it, and I could see this come to pass if everyone gets cell phones and uses them primarily. But until then, your claim is about as odd as asking other people not to notice the RF equivalent of flashlight strapped to your head.

    4. Re:Considerable by Anne+Thwacks · · Score: 2, Insightful
      If you want privacy what the hell are you doing using equipment that broadcasts

      Oh, yeah, PT Barnum described the phenomenon accurately.... there's one born ...

      --
      Sent from my ASR33 using ASCII
  6. Google? by gooman · · Score: 2, Insightful

    So how long until we can get an overlay for Google Earth?

    --
    "Kittens give Morbo gas!"
  7. What's the big deal? by schweini · · Score: 2, Insightful

    Could someone tell me why this is supposed to be such a break-through?
    AFAIK, every GSM network provider has a database of what network-cell their users are in at a given time, and when they make a call, so all these guys did was to map that info onto a map of a city? Doesn't sound THAT innovative.
    On a related note: does anybody know of a J2ME program that reads out where the cell-phone it's running on is located at the moment? i once heard something about a "locationAPI' or something like that, but couldn't find a demo program or more info on that.

  8. research??? by idlake · · Score: 2, Insightful

    What's the intellectual contribution of this research? Mapping data onto city maps is standard GIS usage. It's the kind of information companies use for deciding where to locate cell phone towers, where there are coverage problems, and where there are capacity problems.

  9. Re:Whaaaa by Anonymous Coward · · Score: 4, Insightful

    Because you wankers won't give us your plans for making the wheel. Sure it's old news to you guys, but you're the only ones who know about it. If you published your work and opened up your technology, then this would be old news, but for the rest of the world outside your bubble, this is new and cool.