Rory Sutherland wonders about the virtues of traffic lights that tell drivers how many seconds until a green light turns red, or how many seconds until a red light turns green. They appear to be quite popular in China and Taiwan where according to a Freakonomics reader the green lights that count down to red lights increase accidents at intersections, while the red lights that count down to green lights cut them in half. Essentially, moving drivers try to rush through the intersection, while stopped drivers show more patience before speeding out into it. The photo below, from Chinese expat Stephen Cronin, is an example of the red lights that count down to a green.
Rory dug up a bit more information about the lights and it seems they are mainly manufactured by Chinese companies, including Shenzhen Yuhong Electronics and Hepol Electric Enterprises. This likely explains why the Chinese have been the earliest and most widespread adopter of the lights, although they can be found on most continents by now. The best red light countdown design does not come from a Chinese engineer, but instead a Serbian, Damjan Stanković, creator of the Eko, a red light whose outer edge turns from red to black, shrinking the red circle until it turns to green.
“When you think about it, you don’t need this information counted in seconds, you just need to see the speed of the progress bar to give you an estimate of the time,” Stanković told the Daily Mail. Humans have an intuitive sense of numbers, even when they aren’t looking at them.
Addendum: Counting down to walk would be a good idea for pedestrians too.