In an effort to better understand perceptions of urban safety, researchers Phile Salesses, Katja Schechtner and César A. Hidalgo built an online tool that asks users to compare images from Boston, New York, and the Austrian cities of Salzburg and Linz. In a paper recently published in PLOS ONE, the authors discuss some of the patterns they've observed.
"We found images with trash in it, and took the trash out, and we noticed a 30 percent increase in perception of safety," Salesses says. "It's surprising that something that easy had that large an effect."
"This also means some fairly cost-effective government interventions – collecting trash – could have a significant impact on how safe people feel in a neighborhood," adds Emily Badger. "Ideally, in the future, [Salesses] envisions officials using a tool like this to do cost-benefit analyses of removing trash or planting new trees: Where should cities spend scarce resources to produce the greatest improvements in how people perceive a place?"