In today’s NYT Freakonomics column, Eric Morris makes note of the non-linearity of traffic delays, as evidenced by the smooth-flowing traffic in West Los Angeles this past Monday, Yom Kippur. While there are usually a sizable number of Jewish commuters on these streets, he points out, there aren’t that many that would obviously explain a substantial improvement in overall traffic flow on a religious holiday.
The reason is that a small marginal number of cars can create (or reduce) a traffic delay on a scale disproportionate to their number. It’s the proverbial straw (or last group of cars, in this case) that broke the camel’s back.
Small declines in the usage of shared public resources can create disproportionately large benefits. This is one more reason I’m a fan of congestion pricing and the auctioning of airport takeoff slots.