Showing posts with label pedestrian collisions. Show all posts
Showing posts with label pedestrian collisions. Show all posts

Friday, May 28, 2010

There goes David Brooks again....

When David Brooks cites a stat for didactic purposes, hit the factcheck button.

Today, Brooks undertakes to explain why Bad Accidents Happen to Good Workers, citing several allegedly ineluctable laws of human nature alleged to explain why we're biased toward minimizing risk. Among them:
Third, people have a tendency to place elaborate faith in backup systems and safety devices. More pedestrians die in crosswalks than when jay-walking. That’s because they have a false sense of security in crosswalks and are less likely to look both ways.
As an inveterate New York diagonal jaywalker, I took some satisfaction in this apparent factoid. But then I began to think. Aren't there a lot more people in the crosswalks than outside them? Ten times as many, maybe? Okay, in New York, five times as many?

Google and Wikipedia steer casual inquirers on this question to Tom Vanderbilt's In Defense of Jaywalking, published in Slate last November.  There, lo, I found half my NY conjecture vindicated -- minus any figures as to what percentage of street crossings in the city are outside the lines:

In New York City the Post, quoting numbers from the DoT, said 50 jaywalkers were killed annually; this is a high number to be sure, but just one-fourth the total pedestrian death toll.
I would venture to speculate, though, that well more than one-fourth of NYC street crossings are in crosswalks. Vanderbilt's analysis provides further statistical complexity: