Wednesday, September 09 2015 @ 02:28 PM UTC
Contributed by: B' Spokes
1) It would be darn hard to find any meaningful random sampling of what exactly is a "typical" cyclists exposure to calculate comparative risk from.
2) "2001 National Household Travel Survey was used to estimate traffic exposure" - Oh, lets use "main mode of transportation to work" which represents ~ 25% of all trips as the way to calculate exposure. One way to throw off this calculation is if cyclists did more other trips than riding to work as their motoring counterparts. (See ref#1 for more information on trips)
3) Since we are dealing with small numbers (in comparison) small errors can lead to large errors in the conclusion. For example: If you hear that Baltimore's cycling population has increased 300%, while that is a good thing it is still a lot smaller then other cities its size. Small numbers can change dramatically in terms of percentages but still are basically meaningless when looked at in a different light. ]
You can read Washcycle's take more at face value here: