Tuesday, April 17, 2007

Just for fun: Worry about the things that won't happen!

Here's an interesting column by John Stossel about our propensity to worry about exotic risks and discount common ones. A willingness to be deceived about probabilities was demonstrated by an experiment:
We asked people to put on blindfolds and then to pick up a red jellybean from one of two plates that held a mixture of red and white jellybeans. We offered $1 to anyone who could pick up a red bean.

Here's the catch: While one plate held 20 jellybeans and the other 100, the plate with 20 beans had a higher percentage of red ones. We put up signs that told people this clearly: "10 percent red" of the small plate and just "7 percent red" of the big plate.

Surprisingly, even with the percentage signs in front of them, a third of the people picked the plate with 100 beans.

What people saw overwhelmed their ability to think abstractly about probability. They saw more red on the big plate. It's one reason people obsess about things that have a small chance of hurting them but ignore real threats.

Similarly, he notes, people dread plane crashes, which are rare, but do not fear car crashes which are proportionately common. (Of course, only one third of his subjects actually picked the wrong plate. It is not a universal trait.)

Of course, in life as opposed to experiments, ignoring the odds is often rational: If we can't avoid driving, we must get used to its risks. However, Stossel notes, the preference for worrying about exotic unlikely risks rather than common ones results in some pretty bizarre assessments: Seniors who worry about bird flu may fail to get their common flu shot and end up in hospital.

Of course, we do like a little drama in our lives - but just a little. Worry about exotic but unlikely events provides just that touch of drama without real risk.

I'd rather worry that there is an intruder in the office closet than that there is a big mess I have to clean up. If I think there is an intruder, I am almost certainly wrong, and that's relief, but if I think there is a big mess ...
Next book! The Spiritual Brain: A neuroscientist's case for the existence of the soul (Mario Beauregard and Denyse O'Leary, Harper August 2007).