# UCLA Mathematicians Solve Violent Los Angeles Gang Crime with Math

On October 31, 2011, the Los Angeles Timesfeatured new research by UCLA mathematicians that uses a mathematical algorithm to identify street gangs involved in unsolved violent crimes. Professor Andrea Bertozzi, Assistant Adjunct Professor Martin Short and PhD student Alexey Stomakhin set out to solve the problem proposed by the Los Angeles Police Department to identify the top three most likely gangs responsible for an unsolved crime based on activity patterns in the field data of the Hollenbeck division in East Los Angeles, home to some 30 gangs and nearly 70 gang rivalries. Building on the earthquake model they had previously developed to analyze crime activity between these gangs, the research team set out to solve the inverse problem of identifying which gang might be responsible for the unsolved crimes. The results are promising. About 80 percent of the time, the algorithm places the true culprit in the top three gangs based on simulated data that mimics the field data. The result would be approximately 50 percent of the time with random guessing. The algorithm has the potential to apply to a broader class of problems that involve activity on a social network, including identifying terrorist groups based on their communications activity.

Click here to read about their research in the Los Angeles Times

Click here to read about their research in the UCLA Newsroom

Click here to read their research article in the mathematical journal Inverse Problems