The pros and cons of placebo buttons

Over the course of many years, without making any great fuss about it, the authorities in New York disabled most of the control buttons that once operated pedestrian-crossing lights in the city. Inoperative buttons produce placebo effects of this sort (the word placebo is Latin for “I shall be pleasing”) because people like an impression of control over systems they are using, says Eytan Adar, an expert on human-computer interaction at the University of Michigan, Ann Arbor. New York has similarly stripped crossings of non-functioning buttons, says Josh Benson, the city’s deputy commissioner for traffic operations, though it does retain about 100 working ones.

Source: www.economist.com