For the study, researchers from MIT and North­eastern Uni­ver­sity, in the United States, and the Tech­nion and Ben-​​Gurion Uni­ver­sity, in Israel, had access to three years of anonymized cell­phone meta­data for an uniden­ti­fied “west Euro­pean country.” A total of 12 bil­lion cell­phone calls over that three-​​year span con­sti­tuted the raw data on which the group would be testing their theories.

The study began with the obser­va­tion that no cel­lular provider could pos­sibly mon­itor and ana­lyze meta­data over its entire net­work in real time. But real-​​time analysis is key to dis­cov­ering emer­gency events. So sam­pling tiny sub­sets of meta­data from the network—without ever ana­lyzing the con­tent of the calls and text messages—was really the only way to proceed.


Read the article at IEEE Spectrum →