Bicycle Safety expert : Bicycling on the left half of the

This is quite confusing for me.

I dont understand why the left side is more likely to lead to collisions since only 15,17 and 25% of accidents happened on that side. The remaining happened on the right. So isnt the right more accident prone? Conclusion is not making sense to me

Dear VeritasKarishma IanStewart,

Q1. What is the role of Skeptic here?
I know Skeptic is trying to counter Bicycle Safety expert.
But I don't see how his/her counterargument helps in any way to solve or answer this problem!

Q2. Does Skeptic imply that collisions between bicyclists and automobiles is INDEPENDENT of whether riding left or right? (Because after bicycling on the left was made illegal "there was surprisingly LITTLE DECREASE in collisions". So riding either left or right has no effect at all?)

Thank you!

The skeptic is a distraction for you. You have to focus on the expert's argument and figure out why the data he has given is incomplete (so it cannot be evaluated).
He says " in three different studies of bicycle-automobile collisions , the bicyclist was riding on the left in 15,17 and 25 percent of the cases respectively"
So out of 100 collisions in study 1, in 15 the bicyclist was riding on the left. That seems like a small number. But if we were to know that only 1% people ride on the left but 15% accidents happened with left side riders, then we know that left side riding might be more dangerous. But what if 90% people ride on the left side but only 15% collisions were with left side riders? Then it seems to imply that left side riding is much safer.

Since the % of people riding on left is not given, we can unable to evaluate the argument.

Can anyone explain me the meaning of the question?

One reason the strength of the bicycle safety expert's argument cannot be evaluated is that

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