Cellphone Records Could Help Redraw Bus Routes

IBM researchers say they can use cellphone records to plan better bus routes. The claim comes in a entry for a contest to make the best use of cellphone data.

The competition is titled Data for Development (or D4D) and is run by the Orange cellphone network. It’s published an anonymized dataset covering all calls and text messages involving Orange customers in the Ivory Coast over a four month period. With 2.5 billion records this appears to be the biggest such dataset made publicly available.

Entrants had to write a 250 word description of their research project before getting access to the data. The idea is to find the best use of this data to help “address society development questions in novel ways.” The winners will be announced later this week at a conference at MIT.

The IBM entry takes advantage of the fact that in around 500,000 of the records the data includes the nearest cellphone tower to the person making a call, along with any changes of nearest tower during the call.

IBM used this data to figure out the routes people took while making calls in Abidjan, one of the Ivory Coast’s major cities. This will have covered people on the city’s 5,500 buses, in taxis and in cars.

IBM then cross-referenced this journey data with the existing bus network and traced the likely effects of making 65 changes to the network. It concluded three changes would be most effective: adding two new routes (pictured above in blue) and extending one that’s already used. It said that these three changes would make the average bus journey in Abidjan three times quicker.

The company says that it could come up with more efficient changes if it were able to cross-reference the data with bus timetables. It also says a similar approach could work for finding the best places for electric vehicle stations or developing a bike sharing network.