Mapping Puerto Rico’s Hurricane Migration With Mobile Phone Data

Martin Echenique and Luis Melgar at CityLab: “It is well known that the U.S. Census Bureau keeps track of state-to-state migration flows. But that’s not the case with Puerto Rico. Most of the publicly known numbers related to the post-Maria diaspora from the island to the continental U.S. were driven by estimates, and neither state nor federal institutions kept track of how many Puerto Ricans have left (or returned) after the storm ravaged the entire territory last September.

But Teralytics, a New York-based tech company with offices in Zurich and Singapore, has developed a map that reflects exactly how, when, and where Puerto Ricans have moved between August 2017 and February 2018. They did it by tracking data that was harvested from a sample of nearly 500,000 smartphones in partnership with one major undisclosed U.S. cell phone carrier….

The usefulness of this kind of geo-referenced data is clear in disaster relief efforts, especially when it comes to developing accurate emergency planning and determining when and where the affected population is moving.

“Generally speaking, people have their phones with them the entire time. This tells you where people are, where they’re going to, coming from, and movement patterns,” said Steven Bellovin, a computer science professor at Columbia University and former chief technologist for the U.S. Federal Trade Commission. “It could be very useful for disaster-relief efforts.”…(More)”.