





The scientists would not disclose where the study was done, only describing the location as
an industrialized nation.
Researchers used cell phone towers to track individuals' locations whenever they made or
received phone calls and text messages over six months. In a second set of records,
researchers took another 206 cell phones that had tracking devices in them and got records
for their locations every two hours over a week's time period.
The study was based on cell phone records from a private company, whose name also was
not disclosed.
Study co-author Cesar Hidalgo, a physics researcher at Northeastern, said he and his
colleagues didn't know the individual phone numbers because they were disguised into
"ugly" 26-digit-and-letter codes.
That type of nonconsensual tracking would be illegal in the United States, according to Rob
Kenny, a spokesman for the Federal Communications Commission. Consensual tracking,
however, is legal and even marketed as a special feature by some U.S. cell phone providers.
The study, published Thursday in the journal Nature, opens up the field of human-tracking for
science and calls attention to what experts said is an emerging issue of locational privacy.
"This is a new step for science," said study co-author Albert-Lazlo Barabasi, director of
Northeastern's Center for Complex Network Research. "For the first time we have a chance to
really objectively follow certain aspects of human behavior."
Barabasi said he spent nearly half his time on the study worrying about privacy issues.
Researchers didn't know which phone numbers were involved. They were not able to say
precisely where people were, just which nearby cell phone tower was relaying the calls,
which could be a matter of blocks or miles. They started with 6 million phone numbers and
chose the 100,000 at random to provide "an extra layer" of anonymity for the research
subjects, he said. [read more]
Big Brother is in your pants
Study secretly tracks cell phone users outside US
WASHINGTON AP- Researchers secretly tracked the
locations of 100,000 people outside the United States
through their cell phone use and concluded that most
people rarely stray more than a few miles from home.
The first-of-its-kind study by Northeastern University
raises privacy and ethical questions for its monitoring
methods, which would be illegal in the United States.
It also yielded somewhat surprising results that reveal
how little people move around in their daily lives. Nearly
three-quarters of those studied mainly stayed within a
20-mile-wide circle for half a year.