Mathematicians analyze social divisions using cell phone data

May 17, 2013 by Susan Brown
Squares mark each cell-phone antenna with colors corresponding to communities defined by high volumes of calls between towers.

Differences divide us. Human society fractures along lines defined by politics, religion, ethnicity, and perhaps most fundamentally, language. Although these differences contribute to the great variety of human lives, the partitions they create can lead to conflict and strife, impeding efforts toward social justice and economic development.

David Meyer, professor of mathematics at the University of California, San Diego, has been developing new ways of understanding how characteristics like ethnicity and religion coincide to define communities and ultimately influence our actions.

"I've been thinking about mathematical aspects of for a couple of years," Meyer said. "Civil war results from this. Understanding how civil wars spread relies on understanding social divisions."

Meyer's group of research scientists, postdocs and students in mathematics and political science has developed a new way to characterize the relationships among communities defined by different characteristics such as language or religion.

Their efforts to mathematically describe these different geographies won the prize for Best Scientific project in the French Orange's Data for Development (D4D) Challenge. Their project was recognized at the NetMob conference on May 1, 2013 for proposing an innovative methodology, addressing a new question, and for relevant, original findings.

They validated their approach in Côte d'Ivoire, where French is the national language, yet more than 70 regional languages are spoken as well. Nearly 85 percent of people living there use cell phones.

Using data provided by Orange, they mapped connections among 1216 towers for five months. The volume of calls passed from one tower to the next revealed "communities" of antennas based on strengths of the connections, a geographical map of who talks with whom throughout the country.

"It's a measure of interactions, finely resolved," Meyer said.

They compared this to a second map of which languages are spoken by the majority of people in each region. With 60 different languages spoken by local majorities, the comparison was computationally intensive.

The two maps closely agree. It's no surprise given the likelihood of talking most often with those who share your language, but their measure also sorts out an often-confounding factor: proximity.

"It applies to comparing any two maps," Meyer said. "Nearby locations are likely to be in the same category. Even with this adjustment to the comparison, we found an extremely strong association."

Their results show that telecommunications data could provide information about language communities in places where those languages haven't been studied and mapped as completely as they have in Côte d'Ivoire.

More generally, their method can be used to estimate the significance of associations between geographic divisions that arise from other factors as well.

Explore further: Language diversity will make London a true global player

Related Stories

Language diversity will make London a true global player

May 10, 2012

Understanding linguistic diversity among London's schoolchildren is key for the city's future as a 'global player', research shows. A study funded by the Economic and Social Research Council (ESRC) mapped the distribution ...

Urban languages archive is world's largest

October 18, 2012

A University of Manchester archive set up in 2010 to document, protect and support the languages spoken in one of Europe's most diverse cities, is now the world's largest. The web based Multilingual Manchester, which documents ...

The census has got it wrong on languages

January 31, 2013

The widely reported census figures published yesterday by the Office of National Statistics supposedly gave us all a snapshot of what languages we speak and where we speak them. But the data is woefully inaccurate, says Professor ...

Language by mouth and by hand

April 3, 2013

Humans favor speech as the primary means of linguistic communication. Spoken languages are so common many think language and speech are one and the same. But the prevalence of sign languages suggests otherwise. Not only can ...

Recommended for you

Who you gonna trust? How power affects our faith in others

October 6, 2015

One of the ongoing themes of the current presidential campaign is that Americans are becoming increasingly distrustful of those who walk the corridors of power – Exhibit A being the Republican presidential primary, in which ...

Ancient genome from Africa sequenced for the first time

October 8, 2015

The first ancient human genome from Africa to be sequenced has revealed that a wave of migration back into Africa from Western Eurasia around 3,000 years ago was up to twice as significant as previously thought, and affected ...

The hand and foot of Homo naledi

October 6, 2015

The second set of papers related to the remarkable discovery of Homo naledi, a new species of human relative, have been published in scientific journal, Nature Communications, on Tuesday, 6 October 2015.

From a very old skeleton, new insights on ancient migrations

October 9, 2015

Three years ago, a group of researchers found a cave in Ethiopia with a secret: it held the 4,500-year-old remains of a man, with his head resting on a rock pillow, his hands folded under his face, and stone flake tools surrounding ...

Mexican site yields new details of sacrifice of Spaniards

October 9, 2015

It was one of the worst defeats in one of history's most dramatic conquests: Only a year after Hernan Cortes landed in Mexico, hundreds of people in a Spanish-led convey were captured, sacrificed and apparently eaten.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.