Passing thoughts

Wayne Pein said:

I had a few email exchanges with the author several days ago.

Here's one:

Me: Since you were struck twice in a short period, what is your
explanation? What were the road, traffic, driver, and your conditions?
What did the drivers say if anything?

Response: I was struck by a bus and a truck - both got too close
passing. In normal circumstances I would have been able to move away
when I felt them getting close, but the study being what it was, I
couldn't move every time I felt a vehicle getting close as not only
would I lose those data, they were the most interesting data!

He knows I've written a bunch of papers at www.humantransport.org,
including collision studies. I think his answer to my question was a
dodge. However, if he thinks he could have moved away, they must have
been very very slow. I think it's possible he was passing on the right,
or he's making it up entirely. Definitely aggrandizing.

No, it was part of the study design. He used another device to help him
maintain his lane position. I think he is being reasonable in his
explanation. If he had moved to accomodate the other vehicle, the data
for that pass would have been thrown out of the study. I imagine that
both passing drivers felt that he would adjust his lane position to
accomodate them.

-Buck

Buck said:

Wayne Pein said:

I had a few email exchanges with the author several days ago.

Here's one:

Me: Since you were struck twice in a short period, what is your
explanation? What were the road, traffic, driver, and your conditions?
What did the drivers say if anything?

Response: I was struck by a bus and a truck - both got too close
passing. In normal circumstances I would have been able to move away
when I felt them getting close, but the study being what it was, I
couldn't move every time I felt a vehicle getting close as not only
would I lose those data, they were the most interesting data!

He knows I've written a bunch of papers at www.humantransport.org,
including collision studies. I think his answer to my question was a
dodge. However, if he thinks he could have moved away, they must have
been very very slow. I think it's possible he was passing on the right,
or he's making it up entirely. Definitely aggrandizing.

No, it was part of the study design. He used another device to help him
maintain his lane position. I think he is being reasonable in his
explanation. If he had moved to accomodate the other vehicle, the data
for that pass would have been thrown out of the study. I imagine that
both passing drivers felt that he would adjust his lane position to
accomodate them.

I agree with Buck. HIs explanation sounds reasonable to me. The
general idea is to hold extraneous variables constant, and measure the
item of interest. He was holding his position constant. If he dodged,
we'd miss the important point that at least two drivers gave him
_negative_ passing clearance.

When the full paper appears in print, we'll get more details, but I
seriously doubt he was passing on the right. That makes no sense in an
experiment designed to measure how people pass him!

Let's see what the full paper says.

- Frank Krygowski

Wayne Pein said:

I had a few email exchanges with the author several days ago.

Here's one:

Me: Since you were struck twice in a short period, what is your
explanation? What were the road, traffic, driver, and your conditions?
What did the drivers say if anything?

Response: I was struck by a bus and a truck - both got too close
passing. In normal circumstances I would have been able to move away
when I felt them getting close, but the study being what it was, I
couldn't move every time I felt a vehicle getting close as not only
would I lose those data, they were the most interesting data!

He knows I've written a bunch of papers at www.humantransport.org,
including collision studies. I think his answer to my question was a
dodge. However, if he thinks he could have moved away, they must have
been very very slow. I think it's possible he was passing on the right,
or he's making it up entirely.

His explanation sounds reasonable to me. When riding in city traffic
it's not uncommon for a car or truck to partially pass me and then
start drifting to the right before the pass has been completed. This
normally doesn't lead to a collision since it's easily noticed by the
cyclist but would result in a glancing impact if the cyclist strictly
held his line instead of moving to the right.

Buck said:

Wayne Pein said:

I had a few email exchanges with the author several days ago.

Here's one:

Me: Since you were struck twice in a short period, what is your
explanation? What were the road, traffic, driver, and your conditions?
What did the drivers say if anything?

Response: I was struck by a bus and a truck - both got too close
passing. In normal circumstances I would have been able to move away
when I felt them getting close, but the study being what it was, I
couldn't move every time I felt a vehicle getting close as not only
would I lose those data, they were the most interesting data!

He knows I've written a bunch of papers at www.humantransport.org,
including collision studies. I think his answer to my question was a
dodge. However, if he thinks he could have moved away, they must have
been very very slow. I think it's possible he was passing on the right,
or he's making it up entirely. Definitely aggrandizing.

No, it was part of the study design. He used another device to help him
maintain his lane position. I think he is being reasonable in his
explanation. If he had moved to accomodate the other vehicle, the data
for that pass would have been thrown out of the study. I imagine that
both passing drivers felt that he would adjust his lane position to
accomodate them.

-Buck

Buck,

I know how he conducted his data collection. He told me in detail as you
describe.

It's funny how I've never adjusted my lane position to accommodate
passing. Never. I hold a steady line and ride. If a motorist honks for
me to get out of the way or let me know he is there, I either wave him
by, give the finger, or move even further into the lane depending on the
situation. I do not move over for motorists. Ever. And I've never been
hit in many years of everyday riding on mostly narrow roads.

I think you can see that he didn't answer anything in my questions. He
was more than willing to go into detail and provide relatively lengthy
discussion on other topics, but he dodged on discussion of his hits.

You could be correct in your assessment of how he got hit, but I believe
that however he got hit he is aggrandizing the event. I think they were
very slow speed brushes at worst.

Wayne

Quoted message said:

I do wonder what happened in those incidents. But I won't assume that
both of these events were his fault or that he could have done
something to prevent either one. They are probably just a run of bad
luck. Strange things happen in quick succession sometimes.

Should "bad luck" be a valid statistical factor in a study like this? For
anyone to invoke the "bad luck" clause in an experiment is a flag that the
sample size is too small.

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
Redwood City & Los Altos, CA USA

"Buck" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Quoted message said:

[email hidden] wrote:
...

Quoted message said:

As http://www.zzapp.org/rileygea/itsa/helmet2.htm points out,
information on something as simple as "Was the cyclist wearing a
helmet" is _massively_ unreliable on a national scale. We have no
hopes of sifting existing information to learn even that, let alone
anything more.

I agree completely. The data isn't there.

Frank, how will you claim that this guy's ridiculous
'study' has merit without also coming to the conclusion
that cycling is ungodly dangerous?

At his rate of collision, I would have been struck by
vehicles over 2,500 times so far.

Everyone is focused on the collisions when they should be focused on
the study. I actually bothered to do some digging and discovered that
he has a great deal of cycling experience. Here's what he posted on his
website: http://www.drianwalker.com/cycling.html
Now, how many of the pundits around here have cycled solo across
Europe?

I do wonder what happened in those incidents. But I won't assume that
both of these events were his fault or that he could have done
something to prevent either one. They are probably just a run of bad
luck. Strange things happen in quick succession sometimes.

Most research comes from a passion about a subject. Dr. Walker appears
to be someone with a passion for cycling. He designed an experiment
which had enough scientific rigor to warrant funding. The work was
placed under scientific review and passed for publication. He had a
couple of incidents while conducting the experiments. He had the
fortitude to report those incidents as he should.

When it is published, if Frank and Jobst and whomever else around here
with a background in scientific research start poking holes in the
methodology, then I'll consider there may be a problem with the study
design.

-Buck

I agree with what Buck says. I've never mounted video cameras or
proximity sensors on my bike, however, so these comments are based on
nothing more than my thirty three years of experience commuting, club
riding, tours and endurance events. so take them for what you deem them
worth. But from commuting in Los Angeles during rush hour to pleasent
rides in the Carolina countryside, I have noticed a common phenomenon.

When I hug the curve, drivers are more likely to pass in more
unfavorable conditions, and do so closer. Whereas if I ride out about a
third of the way into the lane this is not the case. Even when I move
over as they approach, they will swing quite wide to go around me (into
the next lane here in the Carolinas), or wait patiently behind me until
they can see far enough down the road so to be sure they can safely do
so.

IOW, they treat me as if I were a slow moving car. As so they should.

- -
Comments and opinions compliments of,
"Your Friendly Neighborhood Wheelman"

My web Site:
http://geocities.com/czcorner

To E-mail me:
ChrisZCorner "at" webtv "dot" net

Quoted message said:

Buck said:

Wayne Pein said:

I had a few email exchanges with the author several days ago.

Here's one:

Me: Since you were struck twice in a short period, what is your
explanation? What were the road, traffic, driver, and your
conditions? What did the drivers say if anything?

Response: I was struck by a bus and a truck - both got too close
passing. In normal circumstances I would have been able to move away
when I felt them getting close, but the study being what it was, I
couldn't move every time I felt a vehicle getting close as not only
would I lose those data, they were the most interesting data!

He knows I've written a bunch of papers at www.humantransport.org,
including collision studies. I think his answer to my question was a
dodge. However, if he thinks he could have moved away, they must
have been very very slow. I think it's possible he was passing on
the right, or he's making it up entirely. Definitely aggrandizing.

No, it was part of the study design. He used another device to help
him maintain his lane position. I think he is being reasonable in his
explanation. If he had moved to accomodate the other vehicle, the
data for that pass would have been thrown out of the study. I
imagine that both passing drivers felt that he would adjust his lane
position to accomodate them.

I agree with Buck. HIs explanation sounds reasonable to me. The
general idea is to hold extraneous variables constant, and measure the
item of interest. He was holding his position constant. If he
dodged, we'd miss the important point that at least two drivers gave
him _negative_ passing clearance.

When the full paper appears in print, we'll get more details, but I
seriously doubt he was passing on the right. That makes no sense in
an experiment designed to measure how people pass him!

Let's see what the full paper says.

Frank, who argues endlessly about how safe cycling is and how "exceedingly
rare" bike falls/crashes/accidents are, now supports a whack-job who says he
got hit three times in only 2500 car-passes.

You couldn't make up this stuff...

BS (well, yeah)

Chris Y.F.N.W. wrote:
I've never mounted video cameras or

Quoted message said:

proximity sensors on my bike, however, so these comments are based on
nothing more than my thirty three years of experience commuting, club
riding, tours and endurance events. so take them for what you deem them
worth. But from commuting in Los Angeles during rush hour to pleasent
rides in the Carolina countryside, I have noticed a common phenomenon.

When I hug the curve, drivers are more likely to pass in more
unfavorable conditions, and do so closer. Whereas if I ride out about a
third of the way into the lane this is not the case. Even when I move
over as they approach, they will swing quite wide to go around me (into
the next lane here in the Carolinas), or wait patiently behind me until
they can see far enough down the road so to be sure they can safely do
so.

IOW, they treat me as if I were a slow moving car. As so they should.

This is my experience also.

Wayne

"Buck" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

What you are suggesting is that the experiment is impossible to conduct
because every cyclist will be "reactive" to some extent. I'd rather see
some data from a single cyclist than a gaggle of cyclists because it is
easier to control all of the potential variables.

No, I didn't suggest that at all. I suggested that it is utterly
inappropriate for Walker to have used himself as the sole subject in this
experiment -- since he was aware of his own hypothesis, and aware of his own
need to produce "good" results to get published --

I suspect Walker intended his study as a pilot study and intended to
replicate it correctly, like he must have learned in grad school if he took
even an introductory social research methods course.

There's nothing wrong with using yourself to shake down the equipment and
the procedure and develop preliminary hypotheses. In fact, it's a darn good
idea. But then you go and do the real study using accepted methods.

But somewhere along the line it got out of hand and he published this piece
of junk science. Perhaps he is under pressure to publish soon to keep his
job.

You are making an important point, though. You are quite correct that the
total number of cyclists involved would probably have to be fairly small,
because you would have to train the cyclists to ride properly (e.g. the
appropriate speed to control, the appropriate width from the curve, how to
read the instrument that tells you how far away you are, etc.). Control of
the measurement is important.

Wayne Pein said:

I had a few email exchanges with the author several days ago.

Here's one:

Me: Since you were struck twice in a short period, what is your
explanation? What were the road, traffic, driver, and your conditions?
What did the drivers say if anything?

Response: I was struck by a bus and a truck - both got too close
passing. In normal circumstances I would have been able to move away
when I felt them getting close, but the study being what it was, I
couldn't move every time I felt a vehicle getting close as not only
would I lose those data, they were the most interesting data!

He knows I've written a bunch of papers at www.humantransport.org,
including collision studies. I think his answer to my question was a
dodge. However, if he thinks he could have moved away, they must have
been very very slow. I think it's possible he was passing on the right,
or he's making it up entirely. Definitely aggrandizing.

I expect you'll be writing to the Journal which has accepted his
article for publication, telling them of your concerns, and asking to
be invited to be on their editorial board.

Mike Kruger said:

But somewhere along the line it got out of hand and he published this piece
of junk science.

Um, are you not aware that the author is not the publisher?

In article <[email hidden]>,

Buck said:

When I move further left in my lane, passing behavior changes. Yes, the
relative position between me and the passing vehicle may be closer.
However, I find that people are more reluctant to pass me illegally.
The two most common illegal passes I encounter are passing in a
no-passing zone, and not moving completely into the other lane when
passing (lane sharing). It is the latter behaviour that my lane
position seems to affect most.

The latter maneouver is a pretty good compromise, when it's
executed well, under safe conditions. The rider gets a comfort
margin of passing distance, and the driver isn't very inconvenienced.
I don't care how far over the line they go, as long as they
don't buzz me.

cheers,
Tom

--
-- Nothing is safe from me.
Above address is just a spam midden.
I'm really at: tkeats [curlicue] vcn [point] bc [point] ca

frkrygow said:

Mike Jacoubowsky said:

But... the study that's needed is a bit more broad-based than whether
wearing a helmet makes a difference or not. What's needed is a study
that simply asks (and answers) the question- "What are the behaviours
while riding a bike that influence your safety vs cars?"

I'm not sure what you have in mind there.

Yes, I think there is value in having Walker's passing distance study
repeated using more riders. But it's not surprising that he did it the
way he did, with just himself as a subject. Getting funding to study
such a thing is probably not easy; so rather than hire a small army of
college students to do the riding, he did it himself.

FWIW, I suspect there will be follow up studies trying to verify his
results. And I suspect a very well-funded study by the Harborview
Institute will claim to disprove it entirely, no matter what everyone
else finds! ;-)

But your more general question, "What are the behaviors while riding a
bike that influence your safety vs. cars?" - how exactly would you
propose to study this?

ISTM that you can't send out a gaggle of cyclists and ask them to all
ride differently. You'll get a multivariate mess of folks riding slow,
fast, close to the curb, away from the curb, straight and steady,
weaving, legally, illegally, etc. etc. If you can somehow measure
results, you'll have a hellacious statistical problem trying to separate
out the influences.

In this particular case you're probably right. But wouldn't it be great
to have bike accidents reported and investigated with at least as much
rigor as is applied to motor vehicle accidents? Most of us with plenty of
riding and advocacy experience know which behaviors cause accidents, but
better data to back this up would go a long way toward building consensus
for better rider and driver education, road design, etc.

Matt O.

Quoted message said:

No. We have data regarding 2,300 vehicles passing a control. The
passing vehicles were the experiment, the cyclist was the control. The
control conditions were changed to see what the experiment participants
(although they didn't know they were participating) would do.

I have serious doubts about the ability of others to reproduce Mr. Walker's
results. Until they do, I am reserving judgement on their validity.

Chris Neary
[email hidden]

"Cycle tracks will abound in Utopia" - H.G. Wells