Study: Safety in Bike Numbers Found on the Streets of Boulder, Colorado

The high mode share of bikers in Boulder, Colorado allowed researchers to verify findings already documented by researchers in Europe.

1 minute read

July 2, 2014, 7:00 AM PDT

By James Brasuell @CasualBrasuell


"A University of Colorado Denver study examining collisions between bicycles and motorists, shows bicyclist safety significantly increases when there are more bikes on the road, a finding that could be attributed to a 'safety in numbers effect,'" according to an article on PhysOrg.

"The researchers wanted to create safety performance functions (SPFs) for bicycles in Boulder. SPFs model the mathematical relationship between the frequency of crashes and major factors related to them. Yet while there are SPFs for vehicles, there are none for bikes."

"The authors created their SPF for Boulder by studying crashes at intersections throughout the city where more than two-thirds of collisions occur. They compared the crash data to bicycle count data."

Thursday, July 24, 2014 in PhysOrg

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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