Stewing in city traffic with nothing but the radio or a smartphone for companionship, it might seem like your trip is a solitary one. But look around at the hundreds of other cars, just like yours, idling nearby. Do you ever wonder who these people are, where they’re going—and if you know them?
Marta González, civil and environmental engineering associate professor, did just that, and her findings will directly affect urban policy and planning. González co-authored a groundbreaking study recently published in Scientific Reports demonstrating that urban networks are not determined solely by geography, as is often suspected, but socially too.
The study extracted phone data from more than 25 million phone users in 155 cities in France, Portugal, and Spain over the course of six months, analyzing seven billion mobile phone interactions. The mode of data collection is revolutionary: In the past, analysts would have relied on travel diaries and anecdotal reporting.
By using phone data, González was able to record individual patterns of movement and also the ways in which interconnected people move in relation to one another. Through this data, González and her team deduced that one-fifth of urban movement is for social purposes.
This discovery will influence urban planning, infrastructure, and the environment. For instance, González is currently working with the metropolitan planning office in the Saudi Arabian capital of Riyadh to help policymakers coordinate a bus system that reflects urban travel patterns. “As the city grows, they envision traffic will only get worse—something that’s very costly in terms of carbon emissions and fuel consumption,” González says. Building a bus system with stops and frequencies that anticipate how groups of people actually travel will hopefully encourage more passengers to use it.
This summer, González is working in Rio de Janeiro, Brazil, upcoming site of the 2016 Olympic Games. The city is trying to coordinate traffic routes, as street capacity will be reduced during the events. Understanding how to encourage travelers to use fewer cars will be key. “I’m analyzing how similar people might have similar mobility patterns. Knowing how people move helps us propose solutions,” such as carpooling, González says.
To that end, a logical outgrowth of her research focuses on networking apps for “the greater social good,” she says. By quantifying how much urban movement is social, it could be possible to pair like-minded travelers through social media apps that increase traveling efficiency. González points to ride-sharing service Uber as a company that leverages this kind of dynamic social mapping.
“The information that we generate can be captured in real time, from people using their devices, and we can actually see mobility in a city. This is the age of instant information, and it can directly affect policy. Imagine you have a set number of people traveling along a certain route, and you want to add an extra lane—this data can tell the mayor that you need it, and you can really quantify the need,” she says. “It’s hugely exciting.”