Jul 15, 2012

The Problem with Statistics

I'm reviewing Pat Hahns' new book, Motorcyclists Legal Handbook: How to handle legal situations from the mundane to the insane, for MMM. As always, I ended up with too many words for the magazine publication. As always, I'm dumping the extra verbiage here, because it's something I want to say. Before I go into full rant mode, I want to be clear that this is a useful, well-written book that most of us can use. Like all of Pat's books (except, maybe, Maximum Control: Mastering Your Heavyweight Bike, which is unintentionally hilarious considering the subject and the author who has used my term "hippobike" as often as me), Legal Handbook is practical, helpful, technically excellent, and damn near necessary for anyone who travels interstate. In fact, I'd recommend it as required reading for the IB folks.

Here's my only conflict with the book, and my excess 400 review words: My biggest disagreement with the whole book is about the state "rideability" rating. Rideability is a statistical evaluation of the "ratio of multi-vehicle motorcycle fatalities to single-vehicle motorcycle fatalities," plus the population density and law enforcement density. Pat claims that "a high ratio, such as 75/25, is bad, as it shows in a fatal accident in that state, it is more likely that the rider got hit by another vehicle rather than simply having an accident on his or her own." I disagree with this conclusion on at least two points.

When I first glanced through a few of the states' evaluations, I took that particular ratio completely differently. I would argue that a low ratio, such as 25/75, is bad because it shows that most of the state's bikers may be drunks and incompetents and tend to ride off of the road on their own accord. Plus, simply noting that a crash was a multi-vehicle event doesn't release the motorcyclist from fault for the crash. 

Second, since most Minnesota motorcycle fatalities occur on rural roads and in small towns, I don't put much into population density as a "rideability' evaluator. Having lived in L.A., where I experienced high population density, I apply even less credibility to the density issue as a riding negative. Nebraska has a really high "rideability" rating, but some of the most insane and incompetent drivers I've ever witnessed were in that state. Driver competence is more important than population density.

 I do agree with the inverse connection between rideability and law enforcement population. However, Iowa's 5th place (lower numbers are better) in law enforcement population does not reflect my Iowa experiences. As best I can tell, every third Iowegn is in a police car. I do anything possible to avoid Iowa, even if I'm travelling to Missouri. The whole state is "erratic," to use Pat's term for unusual laws or enforcement. Texas' relatively benign rideability number must reflect the near-absence of motorcycles from the streets and roads of that state. I lived in Dallas and west Texas in the 60's and 70's and the place was hell on wheels for motorcyclists then. My daughter and her family live in Dallas and I visit fairly regularly. I can count on the fingers of one hand the number of motorcyclists I've seen in the time I've been in Texas in the last ten years. In all, I'd have to put minimal value on the book's rideability estimates. Somewhere in the mix, there would have to be a miles-driven/motorcycle crashes value for that kind of evaluation to be useful.


Anonymous said...

"State rideability" is a silly way of looking at things anyway. For example, New York State includes such diverse places as New York City and the Adirondacks--at polar opposites in terms of rideability. Do you trash New York because of New York City. Any state with big urban areas will suffer because of this, while I imagine some of the Plains states might look pretty good in the ratings, but who wants to ride on straight, flat roads for hour and hour?

Anonymous said...

I can not disagree. Being a native Kansan (a terrible thing to admit), riding across most of the Plains is dangerous because of boredom.