How to use mobile phone data for good without invading anyone’s privacy


Leo Mirani in Quartz: “In 2014, when the West African Ebola outbreak was at its peak, some academics argued that the epidemic could have been slowed by using mobile phone data.

Their premise was simple: call-data records show the true nature of social networks and human movement. Understanding social networks and how people really move—as seen from phone movements and calls—could give health officials the ability to predict how a disease will move and where a disease will strike next, and prepare accordingly.

The problem is that call-data records are very hard to get a hold of. The files themselves are huge, there are enormous privacy risks, and the process of making the records safe for distribution is long.
First, the technical basics

Every time you make a phone call from your mobile phone to another mobile phone, the network records the following information (note: this is not a complete list):

  • The number from which the call originated
  • The number at which the call terminated
  • Start time of the call
  • Duration of the call
  • The ID number of the phone making the call
  • The ID number of the SIM card used to make the call
  • The code for the antenna used to make the call

On their own, these records are not creepy. Indeed, without them, networks would be unable to connect calls or bill customers. But it is easy to see why operators aren’t rushing to share this information. Even though the data includes none of the actual content of a phone call in the data, simply knowing which number is calling which, and from where and when, is usually more than enough to identify people.
So how can network operators use this valuable data for good while also protecting their own interests and those of their customers? A good example can be found in Africa, where Orange, a French mobile phone network with interests across several African countries, has for the second year run its “Data for Development” (D4D) program, which offers researchers a chance to mine call data for clues on development problems.

Steps to safe sharing

After a successful first year in Ivory Coast, Orange this year ran the D4D program in Senegal. The aim of the program is to give researchers and scientists at universities and other research labs access to data in order to find novel ways to aid development in health, agriculture, transport or urban planning, energy, and national statistics….(More)”