The Lean - A statistical factsheet

[bogan]

MAG-NZ have done a stats factsheet and analysis as part of our ACC and Motorcycle safety campaigns.

go to our site to have a look (Factsheet exceeds the file size limit here).

Here's the intro:

Most will be aware of the ‘lean’, or bias, taken with the statistical analysis of motorcyclists accidents in recent times. This fact sheet is intended to provide unbiased data to motorcyclists and anyone else with an interest. We supply this to allow you to make your own informed decision about the risk of motorcycling, so you can choose which way to ‘lean’ and take action accordingly!
The report is split into two sections, Historical Data, and a Current Crash Statistics section that takes a more in depth look at various factors contributory to the accidents.

[porky]

Nice work. Is there further breakdowns. Just curious what the pie charts for fatalities/ injuries would look like seperated out by the motorcyclist at fault vs not at fault and then compare the two.

[bogan]

Nice work. Is there further breakdowns. Just curious what the pie charts for fatalities/ injuries would look like seperated out by the motorcyclist at fault vs not at fault and then compare the two.

yup reading of a graph in the "2008 motorcycle crash statistics" shows that for minor injuries biker fault is just under 50%, serious injuries just under 60% and fatals just over 70%.

We haven't put many in depth analysis's in the factsheet as the data gathered has some inherent limitations. One of these is combining the crashes from scooter with those of motorcyclists, scoots make up around a third of registered two wheelers. Combining motorcycle crash data with a vehicle class limited to 50kmhr (basically inner city commuting) is far from ideal, but you have to take that into account when looking at the more in depth analysis's.
Like the per km figure they have done, it meaningless as they don't compare the same kilometers, their calculated risk per km is 4x greater than the risk per registered vehicle because they have established bikers do 1/4 of the mileage. You gotta ask how many assumptions and data manipulations have they made to assume I do 1/4 of the km that I used to in the car. Have I moved closer to work? or have I stopped going for sunday drives?

[NONONO]

There are so many anomalies in the data that it is statistically useless, but we pointed some of that out to them last time with nil result.
Looking the the stats, the actual "Fault Determination" has glaring holes.
For example, when broken down by license type we have 11% "Unknown".
11% of accidents where the rider's (who was deemed at fault) license type was not known or not recorded. How is this possible?
There is research that points out the data gathering at the accident scene is not consistent. Also that contributing factors are often ignored in favor of a bias towards recording cause (fault).
The stats provided are just too simplistic, too general to have any meaning.
Good to see them so clearly displayed though, good on yer Mr Bogan.

[Katman]

There are so many anomalies in the data that it is statistically useless, but we pointed some of that out to them last time with nil result.

If nothing else, they give an indication of the extent of our problems and the direction we should be looking in.

(Oh, and they also categorically destroy the "it's always the fucking cage drivers fault" fallacy).

[Blackflagged]

Not many would say always.Be interesting to see fault % for car vs motorcycle.And exclude single vehicle accidents.Because car drivers a probable responsible for over 50% also.Intersection still most dangerous for accident, must be all those Motorcycle riders not seeing cars!

Always remember the penalty's for getting it wrong can be quite severe! Big improvement since 1995 though.

[Katman]

And exclude single vehicle accidents.

Far too many motorcyclists are far too quick to ignore the single vehicle accident stats.

(And there's possibly as many 'single vehicle' motorcycle accidents that go unreported as those that figure in those stats).

[bogan]

Not many would say always.Be interesting to see fault % for car vs motorcycle.And exclude single vehicle accidents.Because car drivers a probable responsible for over 50% also.Intersection still most dangerous for accident, must be all those Motorcycle riders not seeing cars!

Always remember the penalty's for getting it wrong can be quite severe! Big improvement since 1995 though.

did you read the whole thing? there's a pie chart which includes that stuff.

Far too many motorcyclists are far too quick to ignore the single vehicle accident stats.

I guess the assumption there is those who consider themselves careful or good riders don't have to worry about single vehicle accidents wonder if theres any stats for single vehicle accidents who considered themselves good/safe riders though...

[NONONO]

Far too many motorcyclists are far too quick to ignore the single vehicle accident stats.

(And there's possibly as many 'single vehicle' motorcycle accidents that go unreported as those that figure in those stats).

Currently looking at research, as I mentioned earlier, that would present a different angle. That CONTRIBUTING factors are often ignored or overlooked in the rush to find cause and therefor by definition fault.
So single vehicle accidents are attributed simply to the rider without any attention being paid to contributing factors.
Now you can argue the point all you like, but the research IS there if you look for it.

[Berries]

wonder if theres any stats for single vehicle accidents who considered themselves good/safe riders though...

You could just look at BMW riders.

[Squiggles]

but the research IS there if you look for it.

I did and came to a similar conclusion to Katman...

[bogan]

I did and came to a similar conclusion to Katman...

more importantly, what do you think of MAG-NZ's interpretation?

[MSTRS:Me]

I did and came to a similar conclusion to Katman...

In a single bike crash, you can only conclude rider fault if you call it rider error. By that, I mean, all those crashes where the rider *should have seen, processed and adjusted for* a threat to his safety. I don't buy that it is possible to do so in a significant number of such cases.
However, I don't mean that a rider is not responsible for their riding. A better standard of roadcraft would see a huge reduction in all types of motorcycle-involved crashes.

[Squiggles]

more importantly, what do you think of MAG-NZ's interpretation?

There isnt much interpretation, more a rehash of what the individual documents state =\

I'd also look at the age of riders and the so called "returning riders". I had a study from Auckland Uni (i think) on that but can't find it now. Very interesting as it put us at the end of that era (meanwhile plenty of funding is being poured into it)

The incident type data shows that intersections and losing control account for a very large proportion of both fatalities and injuries. It is likely intersection accidents will be predominantly caused by other motorists not doing adequate check for bikes, and the loss of control will be single bike accidents.

No need to theorise about fault, the breakdown is listed on page 6 of the MoT Crash Stats 2008.

[bogan]

There isnt much interpretation, more a rehash of what the individual documents state =\

Well yeh, with only general figures available, we could only comment on the general state of things. Would really like to get some more data to work with, especially separate stats for scoots vs motorcycles. But with what I've seen to start getting into detail requires a lot of assumptions...

I'd also look at the age of riders and the so called "returning riders". I had a study from Auckland Uni (i think) on that but can't find it now. Very interesting as it put us at the end of that era (meanwhile plenty of funding is being poured into it)

Be interested to see that study about returning riders if you do come across it.

No need to theorise about fault, the breakdown is listed on page 6 of the MoT Crash Stats 2008.

Right you are