The top posts of 2007: number 6

Over the holiday period, the physics arxiv blog is re-running the most popular blogs (by page views) of 2007.

Cellphone records reveal new patterns of human activity
29 October

Switch yer mobile phone on and it checks into the local network giving your location and the time you were there. The network also records the calls you make, their frequency, duration and to whom you make them plus wherever they happen to be too.

Multiply that by the entire popualtion (mobile phone penetration approaches 100 per cent in many western countries) and you’ve got a data set that can give an unprecedented insight into the links between people and the way they move and behave.

Albert-Laszlo “Bar” Barabasi at Northeastern University in Boston and a few pals have been a-grindin’ and a-crunchin’ the data from several million cellphones and are now revealing what they’ve found.

Turns out the data can be used to identify friends and family (from the frequency and duration of calls and whether they are reciprocated), they can show how social groups evolve and how they fall apart.

The data can also suggests how to monitor the way people behave in emergencies in realtime. For example, a pile up on the freeway causes lots of rapidly moving phones grind to a halt, a few call the emergency services while others call the office/spouse/lovers. Spot that pattern and its a pretty good indication that an event has occurred. Location information might even help to determine exactly where the accident took place.

Barbara Rasi has also found previously unknown patterns in human behaviour. For example, although the number of people making calls varies hugely during the day and night, the percentage who are on the move (ie who make consecutive calls from different lcoations) is always roughly the same. And the average distance they travel between calls in a half hour period is also stable at about 6 km. He says this is just the beginning of what will be possible with this kind of data.

What ya’ll want to know is how anonymous is it? The message is: Big Brother is watching…but he only has access to anonymized data.

But ah don’t buy it. It wasn’t so long ago that the raw data from search engines was thought to be anonymised if a person’s name was removed from it. But that myth was exploded by journalists from the New York Times who tracked down one individual using only her AOL search records.

How long before we see a similar expose with supposedly anonymized mobile phone records?

Ref: Uncovering Individual and Collective Human Dynamics from Mobile Phone Records

2 Responses to “The top posts of 2007: number 6”

  1. barbara says:

    Hi, my name is Barbara Rasi.

    I live in Italy and I am a teacher.

    Surfing internet I came across the lady here mentioned with my name and surname.
    I would like to contact her, if possible.

    Thanks for any answer.

    Barbara Rasi

  2. Drew says:

    Hey Barbara Rasi, I just googled your name because it was my mother’s name. I’ve googled it before, but without any results as recently as 6 weeks ago. It is definitely an unusual last name, there aren’t very many of us here in the US and none are Italian. have a good day