Twitter hailed as 'powerful tool for crime detection'

A study conducted by Matthew Gerber, an assistant professor of Systems and Engineering Information at the University of Virginia showed that Twitter doubles as a social engagement platform, as well as a tool to help predict crime.

Gerber's research and work developing statistical crime prediction methods was presented on Tuesday at the Joint Statistical Meetings in Baltimore.

With inputs from the American Statistical Association, the research work was conducted on Twitter alone owing to its transparency and ease of access to GPS-tagged tweets generated in a given area.

"My initial hypothesis was that there would be no correlation between Twitter use and crime. After all, people don't share with the world that they intend to or have just committed a crime. What they do share are things like social events or outings that could lead to criminal activity," said Gerber.

His statistical method involved collecting more than 1.5 million public tweets tagged with Chicago-area GPS coordinates spanning January to March of 2013, as well as crime records covering the same period and geographic area.

After dividing and mapping out tweets and crime records onto a grid and identifying common topics of discussion appearing in tweets, Gerber combined conclusions from this analysis with older forecasting models to predict crimes over the next month. The result of his combined method was more precise, accurately predicting 19 out of 25 crime types.

There are some cities that utilise such methods as a basis for resource allocation, as a result of which they have seen a drastic decrease in crime. As for the causal connection between tweets and crimes, Gerber admits his method cannot answer that. Even so, it's gaining attention from police departments all over the United States, including Chicago and New York City. His work could further assist departments in resource allocation, deciding where and when to deploy officers.

Gerber co-directs UVA's Predictive Technology Laboratory, which uses data to create predictive models with the goal of promoting better decision making. In addition to applying models to the field of policing, the lab is also conducting research in other important fields like health care and the military.