On the Road

Billboards, distraction and tax revenues

January 6, 2013

You don't need a PhD to recognize that bright flashing lights and changing images will grab drivers' attention. They are supposed to. But since drivers ought to be paying attention to things that are more pressing, why are these signs sprouting up everywhere?

Do these animated electronic billboards distract drivers? (Photo courtesy of adsemble.com)



Do electronic billboards pose a safety threat? There are studies that make convincing cases either way. The results apparently depend on who commissions the research.

Among the studies that fail to come a definitive conclusion, but warn explicitly of the dangers posed by the brightly lit signs, was a study that emerged from Sweden in July 2012. It came to our attention last week in a press release with the heading, "New Study Finds Digital Billboards Distract Drivers."

The press release comes from an organization called Scenic America. The group's mission is to preserve and enhance the visual character of America by safeguarding the scenic qualities of Americas roadways, countryside and communities. They are more interested in preventing the visual blight associated with electronic American highways than they are in driver safety, but they obviously aren't beyond playing the safety card to further their agenda.

But back to safety. The advertising companies and the electronic billboard advocates say the e-billboards are no different fundamentally from a vinyl-clad billboard, except that the message changes. For the advertiser, that means 10 messages a month where there once was one -- or 10 advertisers paying for space where one once footed the bill.

But it's the changing of the message that seems to create the problem.

Do these animated electronic billboards distract drivers? (Photo courtesy of adsemble.com)



The Swedish study, "Effects of Electronic Billboards on Driver Distraction," published in July 2012 in the Journal Traffic Injury Prevention and funded by the Swedish Transport Administration, showed that while some drivers choose to ignore the billboards, others' gazes lingered longer on the billboards, apparently waiting to see what the next message would be.

As background, the authors explain how, consciously and unconsciously, drivers visualize and respond to changing traffic patterns and traffic signs -- and billboards. The way drivers react to each of those inputs is quite different.

Visual, Mental Processing

The way the Swedish researchers describe it, several processes are going on in drivers' minds as they travel along a road. They scan the immediate environment for inconsistencies in normal traffic patterns. They watch for signs displaying information relevant to them while ignoring irrelevant signs and information. For example, they see but immediately dismiss and forget information about a destination other than their own, such as exit signs and off-ramp speeds.

While scanning the horizon for irregularities, they do tend to notice things that they are interested in, or that succeed in getting their attention, over and above the usual visual clutter -- such as brighter-than-usual e-billboards.

The scientists say these responses can be reflexive or habitual or controlled. A reflexive response is involuntary -- something grabs the driver's attention and he or she looks at it. A habitual response has the driver look because it's something out of the ordinary. A controlled response has the driver looking because he or she is interested and wants to look.

The scientists say it's difficult to measure driver response to such stimuli with eye-monitoring cameras because they can't determine which of the three responses occurs in the drivers' heads. The length of time the driver's gaze is averted from the road can be measured, but it's without context. Additionally, they say it's difficult to determine if a driver has in fact been distracted, just because his or her gaze is averted from the road.

Driver inattention has been defined as not paying enough attention -- or not paying any attention -- to activities critical for safe driving. This implies that whether a driver has been distracted or not can only be determined in retrospect, at least if safe driving is defined as the absence of crashes or critical situations.

In that context, given the small number of crashes that result from being distracted by e-billboards, it's hard to make a case against the things.

However, if the billboard absorbs drivers' attention for longer than intended, drivers may become, or be deemed, distracted. And that would appear to be a consequence of the advertisers' ultimate goal. They want their message remembered. To do that they must exert more influence over the drivers' attention than anything else on the visual horizon.

Remember the Message

The Swedish study found that electronic billboards do attract more visual attention than the other traffic signs included in the study. Dwell times are longer, the visual time sharing intensity is higher, very long single glances are more frequent and the number of fixations is greater for the electronic billboards.

Because the information displayed on the e-billboards is known to change every few seconds, the researchers also found they have the potential hold drivers attention over extended periods of time.

That's exactly what the advertiser wants, of course. They need viewers to remember what they saw.

It seems disingenuous at best for the electronic sign industry to claim their billboards pose no threat to drivers, when the ultimate goal is to hold their attention long enough to drive the message into the driver's memory.

The study did indicated that the duration of the message on changable signs had an impact of drivers' dwell times with the signs.

In Sweden the messages change at seven-second intervals, giving the driver ample time to read and digest the message, but too much time to build up expectation over what the next message would be. In the United States, the message duration regulations are all over the map. They range from two seconds to 10 seconds, with some states requiring the sign go dark between changes. All of this affects how drivers respond to the signs and how long they stare at a sign waiting for it to change.

Other forms of messaging seek to engage passing drivers by asking questions and then providing an answer. Given that they are legible from 1,000 feet away or more, the driver has time to spend with the sign, which of course competes for the driver's attention with traffic.

Taxing the Message

Canada's Macleans magazine recently ran a story about cities taxing e-billboards to boost revenue. The magazine reports that the city of Winnipeg, Manitoba, was poised to raise the tax rate on animated digital billboards by as much as 380%. Taxes on animated digital boards would have increased from $1,000 a year to $23,000, Macleans reports.

The city backed down after an outcry from the outdoor advertising industry, but plans to have another go at it this year.

Several U.S. cities, including Baltimore and Pittsburg, have put billboard taxes in place, and are reaping landfall revenues. Pittsburg expects to generate between $2 million and $4 million annually from a 10% tax on billboards.

It's my guess that when more jurisdictions catch wind of the revenue-generating possibilities arising from the changable signage, they will be loathe to pass regulations banning them.

So, dangerous or not, we're likely stuck with them. But hey, there are enough of them around right now, and many, many more on the way if projections from that industry are accurate -- maybe there's a way of supplementing highway funding! Any e-billboard located on an Interstate right of way could either be taxed out of existence or forced to pay huge levies for the privilege of being there.