Tuesday, April 24, 2007

Shared Space, Risk Compensation, and Framing

The concept of "bounded rationality" (Herbert Simon) is a structure for understanding how we cope with the complexity of the world in framing risk management decisions. In the arena of the public sector and public policy, Charles Lindlblom called an earlier but similar notion the process of "muddling through," the idea that decisions are evolutionary and incremental.

A recent risk compensation column states, "That seat belts save lives is, however, completely false. Seat belts, by almost any measure, do not save lives. At best they do nothing. At worst, they actually cause more accidents and fatalities."

In his article, "Cars, Cholera, and Cows: The Management of Risk and Uncertainty," however, John Adams wrote that the use of a seat belt improves a car occupant's chances of surviving a crash. Evans has calculated that wearing a belt reduces one's chances of being killed if in a crash by 41 percent."

Offsetting behavior induced by compulsory seat belt laws ("risk compensation") is the issue that Adams highlights.

Later, in Primatalk, an author wrote, "In fact, the government of the Netherlands is currently removing stop lights from intersections. Apparently they believe Mr. Adams because he is the consultant on this project. The result? an 89% decrease in accidents at intersections that formerly had stop lights."

This concept is called "shared space," and the decrease in crashes in the Netherlands is correct. However, this decrease in accidents is probably due to the lowering of average vehicle speeds (average speed reductions of about 11 miles per hour in congested areas have been observed) [these reductions are buttressed by the Netherlands' risk liability system wherein the vehicle driver is presumed to be at fault in a vehicle-pedestrian or vehicle-cycle collisions]. The risk compensating behavior is slowing down (and fearing the financial (and psychic) consequences of hitting a biker or walker). It's certainly interesting and should be included as a measurable, attenuating impact in risk management mitigations, but, exactly, how is this a revolution in risk management?

There are risk compensating trade-offs involved in police officers wearing body armor, children wearing bicycle helmets, and roofers wearing fall harnesses. How do these change our decision-making processes? Eliminate such devices so that police officers will be less aggressive in apprehending suspects, children will ride more slowly or learn cycling later, and roofers will refuse to work on roofs beyond a certain pitch or demand a higher wage? To me, however, these trade-offs in risk-compensating behavior seem more complex.

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