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Comment by jean_claude | Hacker News Reader

What's your source on the claim that bicycling is 7x more dangerous than driving a car?

Most sources put it around 2.5x more dangerous than driving, and I'd wager most of those deaths come from inexperienced riders who don't know the traffic laws as applied to bicyclists.

Fatalities Per Mile

Motor Vehicle Travel.................... Bicycle Travel

42,000 killed........................... 813 killed

2.56 trillion miles..................... 21 billion miles

0.016 fatalities per million miles...... 0.039 fatalities per million miles

Data from Traffic Safety Facts 1997 and The Environmental Benefits of Cycling and Walking

Pulled from http://www.bellboycott.com/cached/www.kenkifer.com/bikepages...

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Most sources put it around 2.5x more dangerous than driving, and I'd wager most of those deaths come from inexperienced riders who don't know the traffic laws as applied to bicyclists.

Unsure about deaths, but it turns out that more experienced cyclists are actually more likely to be injured, even taking into account that experienced cyclists generally ride more.

I can't find the paper now, but [1] shows a similar finding:

accidents were associated with.... cycling experience (curvilinear association)

[1] https://trid.trb.org/view.aspx?id=1356866

That's interesting. Your comment jogged my memory on a study of how automobile drivers act around bicyclists based on drivers' assumptions about the appearance or perceived level of experience of the cyclist.

According to the research, overtaking vehicles drive closer to better equipped cyclists (wearing a helmet, reflective vest...) than a woman with long hair and no helmet.

Also, the bicyclist with protective gear might be more prone to engage in risky behaviour. http://www.scientificamerican.com/article/strange-but-true-h...

"The implication," Walker says, "is that any protection helmets give is canceled out by other mechanisms, such as riders possibly taking more risks and/or changes in how other road users behave towards cyclists."

most of those deaths come from inexperienced riders

Similar things can be said for driving, in that motor vehicle accidents are concentrated in certain segments of the population, (and people having unlucky interactions with those segments.)

Though this niggle of the statistics is more of an issue with bicycling statistics because the bicyclists who know more or less what they are doing get lumped in with the accident rates of people like the "DUI bicyclist" riding home after dark with no lights into oncoming traffic, or terrible tragedies of people driving carelessly through neighborhoods and running over little kids on their bikes.

Then consider, even if we had statistics showing moderately higher injury/death rates for comparable travel styles with a bike opposed to a car, the overall mortality rates in the bike vs car cohorts would no doubt be reversed because of the physical activity vs sitting factor, and likely lower stress levels of the cyclists. Physical activity tends to reduce stress.

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