The Curious Psychology of Bumper Stickers

While I was out of the country, a new study on bumper stickers was hitting the media. As it touches upon on a number of things discussed in Traffic, the study, “Territorial Markings as a Predictor of Driver Aggression and Road Rage,” by William J. Szlemko, Jacob A. Benfield, Paul A. Bell, Jerry L. Deffenbacher, and Lucy Troup, all of Colorado State University, was right up my alley.

The study, published in the June issue of the Journal of Applied Social Psychology, essentially seeks to explain what part of aggressive driving behavior might be caused by the very environment of traffic, and the way we understand it and inhabit it. Working partly from a previous theory (i.e., I. Altman, The Environment and Social Behavior), the authors delineate the different types of space we inhabit: Primary, Secondary, and Public. A primary territory would be one’s home; a secondary would be a space one inhabits temporarily (the office); while public territory would be a park bench. One interesting source of tension noted by Altman is when one type of space (primary) is adjacent to another (public). When these are adjacent, “the potential for miscommunication and conflict increases as a result of confusion of social norms for each territory type.”

This is exactly the kind of situation we have in traffic: We sit in our own cars, occasionally acting like they are rooms closed off from the rest of the world; but most of the time we drive, save for our own garage, we drive in a public setting. As the authors note, however, some “boundary confusion” exists: “How many times have drivers uttered the phrase ‘He just got into my lane?’ ”

If one of the hallmarks of primary space is a tendency to mark it in some way, to define one’s territory, the authors speculated, then the opportunity for boundary confusion might be highest among those most committed to marking territoriality over their primary space. Thus, they argued, people who personalized their vehicles, and reported showing the most attachment to their vehicles, would act most aggressively to defend their territory in the transitional spaces of traffic.

And this is precisely what they found, in a self-reported survey of college students: “Both number of territory markers (e.g., bumper stickers, decals) and attachment to the vehicle were significant predictors of aggressive driving.”

While I found the study novel in its approach, and its implications fascinating, I was left with a few questions.

First, there’s the obvious shortcomings with self-reported questionnaires (and among small sample sizes of students at one college). The questions themselves often have their own power to influence the answers, and I’m not really sure I would even know how to quantify something like “attachment to my vehicle” on a scale from one to seven (and the answer would certainly have varied last weekend when I had to get new struts put on to the week before, when the car was running well).

Secondly, I’m wondering whether bumper stickers really signify attachment to one’s vehicle. If you’ve just shelled out 75K for a new 7-series BMW, does the driver really show their devotion to that vehicle by putting a $1.50 bumper sticker that says: “Archaeologists Do It in the Dirt”? Purely based on my own experience, I find that older vehicles tend to have more bumper stickers than newer vehicles (because, let’s face it, isn’t a car bearing dozens of bumper stickers really sending the message: “I don’t really care all that much about this car.”). Maybe attachment grows with age (e.g., you call your heap “Old Bessie” or some such), but perhaps with hedonic adaptation the lustful glow of that new car has faded.

Thirdly, my own pet theory is that one of the reasons people put bumper stickers on their car relates to narcissism — another factor that has been implicated in aggressive driving. The person who insists on telling you they vacation at Martha’s Vineyard (those annoying little “MV” stickers) may feel a certain superiority to others on the road, or is the type of person who is not used to having their perceived superiority questioned in other areas of life and so isn’t likely to on the road either. Somewhat relatedly, I’d be curious on the role of “vanity plates” in a study like this; they too would presumably be overrepresented as those claiming more aggressive driving — in either the territoriality or narcissism explantation.

Fourthly, there’s a national issue here that needs addressing, in my opinion. Drivers in the U.S., as any visitor to another country will notice, have a much higher tendency to put bumper stickers on their cars. Are people in the U.S. simply more territorial? Are we still, as a nation, conquering that frontier, staking our claim to our dubiously acquired land gains? Is it a function of our almost fetishistic attachment to free speech? Is there something in our national character that compels us to broadcast our small tokens of identity to an audience that really doesn’t care? If people in other countries don’t really display so many bumper stickers, are they demonstrating territoriality in traffic in some other way, and does it differ from the way bumper-stickered drivers in the U.S. do?

Fifthly, the authors report that the content of the bumper sticker didn’t matter when it came to reporting aggressivity. I wonder if this really tracks to the general population. Are people with NRA stickers really little bundles of altruistic joy on the road, and are people urging us to ‘Practice Random Acts of Kindness’ really always tailgating us and cutting us off? My own experience is an emphatic no, though I may be falling for some as-yet taxonomied psychological bias. I would be curious to see a study that compared crash rates of vehicles with bumper stickers versus those without (this would be very difficult; an easier one would be to measure speed and following distance of vehicles with bumper stickers versus those without).

As an addendum to these last two points, a friend in China reports that a newly emerging custom, in Shanghai at least, seems to involve covering one’s car in, er, cartoons. Comparing the photo below with the one that opened the blog post, are these really part of a similar strategy of territorial marking, betraying similar tendencies toward aggressive driving? Beware the wolf in Hello Kitty clothing…

(P.S. As an another addendum, I recently learned that “do you have a bumper sticker?” and “what does it say?” are common questions in voir dire, or jury selection).

This entry was posted on Monday, June 30th, 2008 at 1:55 pm and is filed under Cars, Drivers, Traffic Psychology, Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

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Traffic Tom Vanderbilt

How We Drive is the companion blog to Tom Vanderbilt’s New York Times bestselling book, Traffic: Why We Drive the Way We Do (and What It Says About Us), published by Alfred A. Knopf in the U.S. and Canada, Penguin in the U.K, and in languages other than English by a number of other fine publishers worldwide.

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June 2008

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