NBC News

Mass shootings spawn subsequent mass shootings, new research finds. The researchers discovered statistical “clusters” of shootings in which four or more people die, the standard definition of a mass shooting. School shootings also cluster, said study researcher Sherry Towers, a professor of mathematical and computational modeling at Arizona State University.

“On average, one school shooting inspires 0.22 other school shootings,” Towers told Live Science. “And on average, one mass shooting inspires 0.3 more mass shootings.”

–  Stephanie Pappas

Source: Mass Shootings Are Contagious