alcanoe

Two articles below on the risks of cycling. The second is less directly related, but it indicates how important it is to get a drivers attention as early and far away as possible.

I've been using from dawn to dusk an ultrabright blinking tail light for all my road riding and a like headlight when in urban areas for years. I've noticed a pronounced effect.

Al

A Different Spin on the Dangers of Urban Cycling

https://online.wsj.com/article/SB1000...editorsPicks_3


Texting while driving more dangerous than thought: study

https://ca.news.yahoo.com/texting-whi...214152197.html

Wogster

The first article gives information in a vacuum, there are a lot of things wrong with what is provided, first is that there is no fault determination, in either case.

Cyclists don't have more carbon in their lungs because of cycling, it's the fact that there are too many motor vehicles sharing the road space, in a confined area. London is 7,825,000 people stuffed into 607 square miles, and even with the high fuel prices in the UK, too many of them use motor vehicles to get around. Another contributing factor the UK still uses more then 66,000,000 tonnes of coal each year, and coal is a dirty fuel.

The second number that is in a vacuum is the NYC pedestrian versus cyclist number, no fault is determined, which is important, how often is it the cyclists fault, and how often the pedestrians. People don't look for traffic anymore, they listen for an internal combustion engine, if they hear one, then they look. This is an issue with hybrids where in electric motor mode, they are nearly silent and with electric scooters as well. Even so, how many pedestrians are hit and injured by motor vehicles in the same geographic area over the same time period. What is interesting is how the number of collisions has not increased much, while the number of cyclists has nearly doubled.

Barrettscv 

Keep in mind the first study has no statistical validity. A small sample group of five suffers from the Law of Small Numbers.

What I'm talking about here are statements (usually in number theory)
that appear to be true for the first five, or first five hundred,
cases, but only "further along the list" does a counter-example appear
that shows that one's original statement is, in fact, not true.

Mathematicians call this the "law of small numbers:" small numbers
do amazing things, and don't always reflect the "true" nature
of a theory.

A simple example: "every odd number is prime."
This is true for 3,5, and 7, and a naive person might then assume it's
true for all primes (of course, this fails for 9).

A better example: "Q(sqrt(d)) is a unique factorization domain."
This is true for 0<d<40, I think, but it fails at d=40.

The same issue holds true for statistics used in Social Studies. Only a large enough group, randomly selected, provides enough data for generalizations.

Also, the study was conducted in London. The use of older Diesel powered cars in the UK is widespread. Older Diesel motors produce far more particulates than the gas powered cars favored in the U.S.