Skip to main content

Urban planners often talk about ‘urban experiments‘ but developing and executing high quality urban experiments is very difficult. In my past writings, both in blog posts and academic articles, I have argued that urban planners could learn much more about how cities work if we more open to experimentation.

In this post I am excited to share an innovative example of how experimental thinking can be used to learn about city dynamics. This work, led by PhD Candidate Gurdiljot Gill and under the lead supervision of Dr. Alexander Bigazzi at the University of British Columbia (UBC), examined how we perceive  automated vehicle technology, and particularly their effects on pedestrian comfort and safety. The TransLink-funded study engaged 1,133 participants from across British Columbia and aimed to assess public sentiment toward self-driving vehicles (SDVs).

We developed a novel deception-based experiment within a web survey to measure the Autonomy Bias (i.e., examine if people perceive pedestrian-SDV interactions as more or less comfortable and safe than pedestrian-HDV interactions, controlling for all other differences). In the experiment, all 1133 survey participants from British Columbia watched the same 8 video clips of pedestrian-vehicle interactions at crosswalks. We described a random half of the interacting vehicles as SDVs, and the other half as HDVs (all vehicles were in fact HDV). Each participant assessed the comfort and safety of those interactions and we developed statistical models to quantify each participant’s Autonomy Bias.

The unique deception-based experimental design allowed us to isolate the bias effect of vehicle autonomy on comfort and safety perceptions, which we report as the additional seconds of passing time that would generate an equivalent effect on perceptions of safety and comfort.

Key takeaways from the study include:
– 41% of participants felt that pedestrians faced reduced safety and comfort level in SDV interactions compared to human-driven vehicles, while 34% viewed SDV interactions more favourably;
– Participants are split in allowing SDVs on public roads (55% support allowing shared SDVs) but there is a clear consensus on regulations (92% of participants support requiring SDVs to be clearly identified, 89% require a person in the driver’s seat, and 72% do not support SDVs going near pedestrian priority areas); and
– To address the safety concerns of interacting road users, researchers propose a gradual introduction of SDVs—starting with a controlled pilot testing phase.

To read more about the methodology, results, and policy recommendations, visit the study page on our website:

Also, check out these interviews with:
· Global News ( ;
· City News (; and
· CKNW – The Jas Johal Show (

Leave a Reply