Clear Channel advertising at a tube station
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Headquarters: San Antonio, United States
Founded: 1901 (as Foster & Kleiser)
Industry: Out-of-home advertising

Clear Channel Outdoor Holding is one of the world’s largest outdoor advertising companies with close to half a million print and digital displays in 31 countries. Learn more at

Subway advertising tested with eye tracking

Public transport systems are a popular location for out-of-home advertising, they provide a captive audience for advertising messages as people wait for their train or bus, but they also compete with other messages relating to wayfinding and transit information. Digital signs provide a dynamic and engaging medium to convey advertising, but how much do people pay attention to them during their daily commute?

"Tobii eye tracking research helped us answer important business questions about the effectiveness of digital advertising signage."

Kristina Norman

Head of Analytics, Clear Channel

The question

Clear Channel Sweden wanted to understand the effectiveness of its digital displays inside subway stations and how people interact with them and other signage or distractions. The company was interested to know how often they are viewed, for how long, and how this compares to other signs inside the station.

The method

Forty people participated in the study and were fitted with eye tracking glasses and asked to navigate from the street to their platform. The wearable eye trackers recorded the environment surrounding the participants as they walked through the station and tracked their gaze as they looked at their surroundings. The data relating to visual attention on digital signs was then analyzed to deliver answers on what signs were viewed, what elements were seen, and how long participants focused on them.

The outcome

The results showed that 95% of travelers viewed at least one of the digital signs while 83% looked at three or more. This information was used in conjunction with questionnaires to establish opinions towards the digital signs. The study also found that more than half of the respondents were open to the idea of having more digital signs in places such as subway stations giving Clear Channel objective data to base future investment decisions on.