How Aaron Clauset discovered a pattern behind terrorist attacks...and what it told him

It's an idyllic summer day in Denver. Families are enjoying a festival in Civic Center Park, while residents and visitors alike happily stroll along the 16th Street Mall as a shuttle glides past. The air is filled with the sounds of people laughing and children playing.

Suddenly, there's a deafening explosion. The urban tranquility is replaced by scenes of horror: charred wreckage, collapsed buildings, bleeding victims. Horrified screams mingle with the wail of police sirens.

Aaron Clauset watches as this terrorist attack unfolds. The University of Colorado professor is visiting the Counterterrorism Education Learning Lab, a museum that opened near Civic Center Park in 2008. The nonprofit CELL is dedicated to preventing terrorism through education and empowerment, but judging from its centerpiece exhibit — a multimedia display that uses video projections and hidden speakers to make visitors like Clauset feel as if they're experiencing a terrorist event in the middle of Denver — that education and empowerment comes with a heavy dose of anxiety and hysteria. At the end of the simulation, an ominous message lingers on the wall displays: "Terrorism: It could happen anywhere. It could happen here."

"The intent here is to scare you," says Clauset. "This is exactly what the public discourse around terrorism looks like." The underlying message of the CELL and other institutions devoted to terrorism is that it's the great horrific unknown. Terrorism is something that can happen anywhere, at any time, to anyone. Terrorism is something that should be feared, something that should be fought against, but not something that can be fully understood.

Clauset knows that the truth isn't so simple. The unassuming 34-year-old data-sciences whiz kid, dressed in a T-shirt and shorts for this visit to the CELL, understands terrorist attacks better than almost anyone. An assistant professor of computer science, Clauset is based at the BioFrontiers Institute, CU's state-of-the-art bioscience hub, even though he hasn't taken a biology course since tenth grade. This August he'll be presenting some of his newest, most provocative research at the American Statistical Association's Joint Statistical Meetings, the largest and most prestigious gathering of statisticians in North America, though he's never taken a statistics course. And his research on terrorism, which has caught the attention of national-security experts (if not many security officials), provided the basis for a chapter on violent conflict in superstar statistician Nate Silver's bestseller The Signal and the Noise — despite the fact that Clauset attended a small college devoted to the Quaker ideals of peace and consensus.

"In this game, I don't know anyone else like him who has made the contributions he's made to the world of data science across such really, really different disciplines," says James Martin, Clauset's computer-science department chair.

The reason that Clauset's research interests are so disparate — from player dynamics in online video games to the evolutionary forces that determine animal sizes — and his findings so attention-grabbing is because he's dealing with the promise and challenge of "Big Data," the phenomenon in which we now have more information about nearly everything than we have tools with which to understand it. "The science of the 21st century will be understanding complex data," says Clauset. "Today we are pretty good at producing huge amounts of this kind of data, but data alone isn't useful. How do we translate this information into something worthwhile, something scientifically useful?"

Clauset has proven to be exceptionally gifted at turning this data into knowledge, especially in the area of human violence. He's uncovered a statistical pattern behind the frequency and severity of all terrorist attacks, an underlying structure that connects small, isolated bombings half a world away to the catastrophe that was 9/11. The discovery could prove a boon for policy planners around the globe, especially since it doesn't involve any of the private Internet, phone and financial data-tracking for which the National Security Agency is currently under fire. Clauset's work adds a level of scientific objectivity to the guesswork and strong emotions that usually surround the topic of terrorism. But his research also hints at what sort of terrorist attacks might lie in the future — and some of his findings could be more frightening than anything at the CELL.


Aaron Clauset's world is defined by data. The walls of his research lab at CU are covered with dry-erase boards tattooed with lengthy equations and dashed-off graphs, and his conversations with students focus on things like data-mining the complete works of Shakespeare in order to uncover the structural similarities between the plays. "He's always finding fun excuses to look at the world using mathematical tools," says Abigail Jacobs, a third-year Ph.D. candidate in computer science.

Clauset applies those same tools to his personal life. He tries to remain as analytical as possible when he discusses the time in 2004 when he was cajoled into trying out for a reality show and ended up doing a short-lived stint on Average Joe, in which he and a bunch of other regular guys vied for the affections of a model. "I went in thinking this would be a unique experience and fun and weird and an opportunity I shouldn't say no to," he says thoughtfully. "The best thing that came out of it was how much joy it provided to my friends and family."

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Joel Warner is a former staff writer for Westword and International Business Times. He's also written for WIRED, Men's Journal, Men's Health, Bloomberg Businessweek, Popular Science, Slate, Grantland and many other publications. He's co-author of the 2014 book The Humor Code: A Global Search for What Makes Things Funny, published by Simon & Schuster.
Contact: Joel Warner