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Jokes about BMW drivers being, on average, somewhat less than courteous are fairly common. They often run along the lines of, “Despite its good brakes, a BMW will usually stop with a jerk.” Sometimes the language is more colorful.

Now scientific research supports the unwritten and broadly circulated theory that people in BMWs are lacking in road manners. Paul K. Piff, a researcher at the Institute of Personality and Social Research at the University of California, Berkeley, has conducted a study linking bad driving habits with wealth.

The traffic study, part of a larger body of research relating behavior and wealth, pitted pedestrians against passing motorists. It was published in The Proceedings of the National Academy of Sciences in 2012.

In California, where the study was conducted, state law requires motorists to stop at crosswalks when pedestrians are present, allowing them to cross the road. Mr. Piff said his team selected a specific crosswalk to observe, then had a pedestrian appear on the edge of the curb as a car approached. As the pedestrian stepped into the road, a researcher marked down the driver’s reaction to the pedestrian. This was done with 152 drivers.

The team also watched a four-way-stop intersection over a week, noting how likely drivers were to cut in front of others when it was not their turn to go. In their observation of 274 cars, the researchers found that the more expensive ones were more likely to jump their turns in the four-way rotation, Mr. Piff said.

In addition to describing drivers’ behavior in both locations, the researcher was to indicate the sex and age of each driver as well as the age and appearance of the cars, with a “1” signifying beat-up, low-value cars and a “5” given to top-of-the-line models from the likes of BMW and Mercedes-Benz.

Mr. Piff said about eight of every 10 cars “did the right thing.”

“But you see this huge boost in a driver’s likelihood to commit infractions in more expensive cars,” he said. “In our crosswalk study, none of the cars in the beater-car category drove through the crosswalk. They always stopped for pedestrians.”

The study also found that male drivers were less likely to stop for pedestrians than were women, and that drivers of both sexes were more likely to stop for a female pedestrian than a male one.

“One of the most significant trends was that fancy cars were less likely to stop,” said Mr. Piff, adding, “BMW drivers were the worst.”

In the San Francisco Bay Area, where the hybrid gas-and-electric-powered Toyota Prius is considered a status symbol among the environmentally conscious, the researchers classified it as a premium model.

“In our higher-status vehicle category, Prius drivers had a higher tendency to commit infractions than most,” Mr. Piff said.