Stopping Crime Before It Starts

Minorityreport Risk terrain modeling maps various risk factors to identify areas where crimes are more likely to occur. For example, Rutgers University computational criminologist Joel Caplan mapped for Irvington, New Jersey four crime risk factors correlated with shooting incidents. The risk factors were the locations of gang member residences, public bus stops, schools, and facilities like bars, clubs, fast food restaurants, and liquor stores. He found that “the likelihood of a shooting happening at particular 100-foot-by-100-foot places in Irvington during 2007 increases by 143 percent as each additional risk factor affects that place.”

In June, Brantingham and his colleagues published a study that applied Lotka-Volterra equations used by biologists for decades to determine the hunting ranges of animals in the wild to map the territories of street gangs. Their model predicted that 59 percent of gang crimes would occur within two blocks of a border between two gangs and 87.5 percent would occur within about three blocks. When the researchers mapped more than 500 crimes attributed to 13 gangs in a specific area of Los Angeles, they found in fact that 58 percent and 83 percent occurred within two blocks and three blocks of a border respectively. “You would think that we're more complicated than other animals, so a model this simplistic shouldn't work, but I was surprised that it fit as well as it did,” said study co-author Martin Short, an assistant adjunct professor of mathematics at UCLA in Wired UK.