Why People Choose to Live in Harm's Way

"It's likely that people who live near heavily wooded areas in California focus on things they love about their location, like environmental beauty or proximity to the ocean, and simultaneously discount the risk of wildfire," said Jacqueline Meszaros, program director for decision, risk and management sciences at the National Science Foundation.

One study last year found that serious risk-takers seem to follow in their parent's footsteps.

But all humans face choices about risk. And researchers in various studies have found people link perceived risk and perceived benefit to emotional evaluations of a potential hazard. If people like an activity, they judge the risks as low: That shiny red Corvette won't get stolen; this woodsy home with the beautiful view isn't likely to burn down.

If people dislike an activity, on the other hand, they judge the risks as high. Flying, for anyone terrified at the thought, is often thought to be very dangerous, even though it's far safer than traveling by car.

"One of the exciting things in the current generation of research is that emotional components of risk decisions are beginning to be understood in addition to other more established components," Meszaros said. "Turns out that emotions explain a fair amount of what surprises us about people and risks."

Scary studies and useful, cautionary information seem to have little effect.

"We have a number of findings that suggest facts alone often are not enough to change peoples' perceptions of risks," Meszaros said. "People need to relate to those facts at an emotional level for risk judgments to be affected."

• Bad Habits: Why We Can't Stop
• Natural Disasters: Top 10 US Threats
• 101 Amazing Earth Facts