My father hated bumper stickers. He thought they looked trashy.

I don’t mind them — reading bumper stickers gives me something to think about in traffic. Such as, if your car will really be unmanned in case of the Rapture, can you please let me get ahead of you?

It turns out that some types of people are more likely to have bumper stickers than others — and some kinds of bumper stickers are more likely to tick off other drivers, according to a national survey.

A survey of more than 2,000 Americans found that women are more likely than men to have a bumper sticker, by 63 percent to 50 percent. Southerners are the biggest fans, with more than two out of three decorating their chrome in Louisiana, Kentucky, Alabama, Mississippi and Tennessee, according to the survey, which was conducted by Cheap Car Insurance, a Utah-based comparative services company.

Drivers in our more reserved Great Lakes region were the least likely to sport bumper stickers at about 49 percent, the survey found.

As for the stickers’ content, negative perceptions of bumper stickers far outweigh positive responses in most cases, said Jamie Linn, project manager for CheapCarInsurance.net. Linn said the main benefit to going without bumper stickers may consist of avoiding the judgment, or even anger, of other drivers.

"That being said, there’s no evidence that these negative responses actually imperil drivers in any way by leading to real conflict on the road," Linn said.

Some bumper sticker are more likely to agitate other drivers, the survey found.

If you have a Trump/Pence sticker, 28 percent of survey respondents will think you are ignorant, 18 percent will think you are obnoxious or annoying and 8 percent will think you’re aggressive, the survey found. On the other hand, 35 percent considered such a sticker an expression of opinion or pride, 7 percent thought it normal or reasonable and 3 percent thought it was smart and considerate.

There were more negative responses to Confederate flag bumper stickers, with 34 percent of drivers finding a driver with such a sticker ignorant, 17 percent finding such a driver obnoxious and 11percent calling the driver aggressive. One percent of respondents found it funny, the study found. Fans of "The Dukes of Hazzard" are out there.

Pro-gun stickers garnered the most negative responses, with 74 percent of respondents thinking that someone with such a sticker must be ignorant, obnoxious or aggressive.

Bumper stickers that drew the most positive or neutral responses in the survey were ones that expressed support of U.S. troops — 51 percent saw it as an expression of opinion or pride, 28 percent thought it was normal or reasonable and another 9 percent thought it was smart and considerate. Just 6 percent found it annoying.

The ubiquitous "parent of an honor roll student" sticker produced mixed results — almost 52 percent of respondents saw them as an expression of pride or opinion. But nearly 21 percent find the brag stickers annoying, which would explain parodies like "My kid can beat up your honor student" or "My dog is smarter than your honor student."

The survey also found that drivers affiliated with the Green Party were the most likely to have some kind of bumper sticker, at 82 percent, followed by Republicans at 61 percent and Democrats at 56 percent.

Overall, the most popular stickers were those associated with sports, fitness, or leisure activities at 17 percent, followed by politics at 16 percent and college or humor at 15 percent.

A 2008 Colorado State University study found that people who have bumper stickers or vanity plates on their cars were more prone to road rage, no matter what the stickers said. The study cited territoriality — a person with a bumper sticker may regard his car as an extension of his home turf which must be defended.

Will a bumper sticker hurt a vehicle’s resale value? Linn said that it is probably best to remove it before attempting to sell your car.

"While they may personalize your ride while it’s yours, they certainly emphasize that the vehicle is used in the eyes of buyers," Linn said.

Joe Wilson, vice president of merchandising operations at CarMax, the used car retailer, said a sticker will likely not affect a vehicle’s resale value if it is removable material that will not damage paint. But this can vary depending on the type and age of the car.

For example, a removed bumper sticker that reveals a darker spot of paint due to protection from fading will not affect the value of a 10-year-old car as much as it would a newer, more expensive model. Wilson said that mileage, year and how well a car has been maintained are what most impacts resale value, and usually not minor imperfections.

So, get a bumper sticker if you must. But know that you may be getting judged by other motorists.

Personally, my favorite sticker says, "Visualize using your turn signals."

Elmhurst ‘diamond’ interchange opens

This Friday, traffic crossing I-90 on the Elmhurst Road Bridge will start being shifted to a new "diverging diamond" configuration, in preparation for the full interchange to open next week, an Illinois Tollway spokesman said.

The ramps carrying traffic to and from the east will reopen June 19 after being closed for more than a month, Tollway spokesman Dan Rozek said. This will be followed by the opening of two new ramps going to and from the west later next week.

A "diverging diamond" flips traffic onto the other side of the road to allow drivers to make left turns onto the Tollway or Elmhurst Road without cutting in front of oncoming traffic. Right turns onto the Tollway or Elmhurst Road will be made as usual, with traffic controlled by signals.

The $54 million interchange project also will have a shared-use path for pedestrians and cyclists in the median of the northbound bridge. Cars with I-PASS will pay 55 cents to use the new ramps, while trucks will pay $1.70 to $4.50 during daytime hours.

Diverging diamond interchanges are designed to be safer and take up less space than cloverleaf designs. Another Chicago-area diamond is at Route 59 and I-88 in Naperville.

Dump the pump

One way to avoid bad traffic is to not drive. On Thursday, the Regional Transportation Authority will join the CTA, Metra and Pace in celebrating the 12th annual "Dump the Pump Day," a national initiative that promotes public transportation.

During morning rush hour Thursday, Cubic Transportation Systems, the developer of the Ventra fare system, will offer free coffee to transit riders who show a Ventra cardor mobile app or a Metra ticket at the Northwest Transportation Center in Schaumburg, the CTA Roosevelt Station and near Ogilvie Transportation Center and Union Station in Chicago.

A two-person household in the Chicago region can save more than $11,000 annually by downsizing to one car, according to the RTA. Public transit use in the U.S. also reduces the nation’s carbon emissions by 37 million metric tons a year, the agency reported.

It’s also the start of "Bike to Work" week Friday if you want to skip motorized vehicles altogether.

Bike lessons

It’s not too late to learn — the Chicago Department of Transportation is offering free bike riding classes for adults this summer starting this week.

Divvy will provide the bikes. Participants in the classes, which run from 6 p.m. to 8 p.m. on Mondays, will receive a free helmet from Blue Cross Blue Shield. The classes are open to children if space is available, but anyone under 16 must bring a bike.

Classes will be held at the Chicago Center for Green Technology at 445 N. Sacramento Blvd. on June 12 and 26; July l0 and 24; and Aug. 7 and 21. Classes also will be at Kennedy-King College at 710 W. 65th Street on June 19; July 3, 17 and 31; and Aug. 14 and 28. Call 312-744-8147 for details or to RSVP.