The study, titled “Evidence for a conserved quantity in human mobility’ is published in Nature Human Behaviour is based on analyses of 40,000 people’s mobile traces collected in four different datasets.
It is also the first of its kind to investigate people’s mobility over time and study how their behavior changes.
Behind the project are Dr. Laura Alessandretti and Dr. Andrea Baronchelli, researchers in the Department of Mathematics at City, University of London, together with Professor Sune Lehmann from DTU Technical University of Denmark and the research team from Sony Mobile Communications.
“We first analysed the traces of about 1000 university students. The dataset showed that the students returned to a limited number of places, even though the places changed over time. I expected to see a difference in the behavior of students and a wide section of the population. But that was not the case. The result was the same when we scaled up the project to 40,000 people of different habits and gender from all over the world. It was not expected in advance. It came as a surprise,” says Dr. Alessandretti.
Old places disappear
The study showed that people are constantly exploring new places. They move to a new home, find a new favorite restaurant, find a new bar, or start going to another gym, etc. However, the number of regularly visited places is constantly 25 in a given period. If a new place is added to the list, one of the places disappears.
The pattern is the same when the researchers divide the locations into categories based on how often and how long time they spend at the location.
“People are constantly balancing their curiosity and laziness…