Most think they are only 2 feet long

Feb 3, 2009 10:07 GMT  ·  By
White street lines tend to be between 10 and 15 feet long, even tough they only appear to measure 2 feet in length
   White street lines tend to be between 10 and 15 feet long, even tough they only appear to measure 2 feet in length

Most drivers or commuters think that the white lines painted on the public roads are approximately 2 feet long, according to a new scientific research. This means that all these drivers actually mix up their reference points, and are more likely to be speeding than they themselves think, as the mandatory length for these white stripes is 10 feet (roughly 3 meters). The new paper, led by Ohio State University Mansfield campus assistant professor of psychology Dennis Shaffer, and published in a recent edition of the journal Perception & Psychophysics, urges drivers to carefully reassess their behavior on public roads, in order to ensure their safety, as well as the safety of others.

The length of the white lines seems to get bent the faster we go. With increased speed, our eyes play tricks on us, and we seem to perceive these lines as being shorter than they actually are. If you start seeing them moving after each other very fast, like they are only a few inches long, then that's a good sign that you're speeding a lot. The brain is fulled by this optical illusion, but, for most drivers, no alarm signals are raised. Some have learned these signs and have reached a point were they can adjust their speed visually, based on the speed and size of the lines.

However, for most individuals, mastering this is still a challenge, so they continue to drive faster than is safe, both for them and pedestrians. This is especially dangerous on long roads, where interminable hours of driving can take their toll even on the most experienced drivers. Thus, they forget to check the speed gouge, as well as the lines on the road, and keep their vision oriented ahead. This can be very tricky, in the strictest of senses, in that, if you look through the windshield, the lines appear to move a lot slower than they do at the side of the car.

"We were surprised, first, that people's estimates were so far off, and second, that there was so little variability. This means that to most people, 40 feet looks like a lot less than 40 feet when they're on the road. People cover more ground than they think in a given period of time, so they are probably underestimating their speed," Shaffer says. "It was ridiculous. We talked to different people in different states, over different years, and whether the lines were 15 feet or 10 feet, people still estimated them to be two feet."

"Even if you know how long they are, they still look two feet. To have a correct perception of the size of an object, you have to be familiar with the object in advance. And that's the clincher. Very few people are familiar with the size of a line on the road in advance," the researcher concludes.