A guest post by Andrew Shipp; original draft May 15, 2013 on the Econ 244 blog
Florida revealed a scheme to shorten yellow light times. The reduced intervals have, in some areas, doubled the tickets given to citizens for running a red light. According to one Dept of Transportation official, the practice may raise money for the state but makes traffic extremely unsafe. "A one-second increase in yellow time results in a 40 percent decrease in severe red-light related crashes." In some communities the yellow light interval change was below the nationally mandated minimum time limit. After that was discovered, the counties upped the time back to national levels but did not tell the drivers who were ticketed under the old light time.
(WTSP 10 News followed the story.)
The Prof notes that in some countries traffic signals include time remaining,
and drivers are off the moment a light turns green. Woe to anyone who fails
to stop in advance of a light turning red!