Our skewed perceptions of risk

From yesterday’s Independent:

“Professor Gerd Gigerenzer, an expert on the psychology of risk at the Max Planck Institute for Human Development in Berlin, has published a new study into how travel behaviour of Americans changed in the months after the 11 September attacks. Domestic air-passenger miles fell roughly 16 per cent in the final quarter, compared to the previous year, according to the Air transport Association, the trade organisation of US airlines. Americans switched from flying to using the roads to avoid the risk of being taken hostage by terrorists on planes and sent crashing into buildings.

Professor Gigerenzer demonstrates that, as a direct result of this switch, the number of fatal car crashes increased significantly in the last three months of 2001 compared with the same period in the year before. Because of the extra road traffic, 353 more people died in traffic accidents than would otherwise have done, a rise of 8 per cent.

‘This number of lost lives is an estimate of the price Americans paid for trying to avoid the risk of flying’, Professor Gigerenzer says. It is sobering to consider that the risk the millions of Americans were trying to avoid in not flying, and driving instead, was that of the fate suffered by 266 passengers and crew members on board the four flights that crashed. In other words, more people died in trying to avoid the fate of becoming victims of terrorism than died on board the ill-fated planes”.