[Sigia-l] Counterintuitive

[Matthew deStwolinski]

There was a much longer and better article written about this in Wired
magazine two or three issues ago.  It included a number of before and
after statistics that showed significant safety improvements with his
designs.

Here's a link to the abbreviated online version:
http://www.wired.com/wired/archive/12.12/traffic.html


Yogesh Tadwalkar writes:

< 1. No one can set expectations or form habits. Nobody is sure what's
going 
< to happen the next moment, neither drivers nor pedestrians. 

The lack of expectations and habits is exactly one of the things that
makes this new design safer.  When you don't know what to expect and are
forced to act to a new situation each time, you pay attention.  Drivers
and pedestrians paying attention make things safer.  Expectations and
habits tend to decrease attention.

< This will undoubtedly slow the speed of cars as well as pedestrians. 
< Considering this is a 'busy  intersection'  - this will cause
congestion
< and pollution.

It's not like the comparison is between this "slow speed of cars" and
whizzing through green lights.  At traffic lights, the aspect that adds
the most to average time to get through is the amount of time cars must
spend at a stop.  The longer the light stays red in one direction, the
longer the average wait.  Monderman's design takes away any long periods
of stopping for cars or pedestrians.  Instead, they're replaced with
very short negotiations based on eye contact with no wasted time at
moments where there is not a conflict of who's passing through a given
space.  The fact that cars slow down as they approach Monderman's
intersections gives more time for these negotiations to take place
before the juxtaposition would happen, which in turn leads to fewer
times when either party actually has to stop.  Instead, they can make
subtle adjustments to their speed to avoid the actual conflict.  In my
neighborhood in Seattle, we have a mix of regular (but stop sign-free)
intersections and ones with very small traffic circles in the middle.
The ones with traffic circles are much easier to get through when
there's traffic exactly because drivers adjust slightly so as to time
their passing well.

For another example, think of rush hour freeway traffic.  Which do you
think moves faster...traffic that moves along consistently at half the
speed limit or traffic that zooms along for a few hundred yards and then
comes to a complete halt.  The reaction delays of people then speeding
up once the person in front of them starts moving again add up
considerably and provide a good deal of the overall additional time you
spend in rush hour traffic.

< 2. No rules situation loads working memory beyond what's necessary.
Now 
< speaking on cell phones while driving (something people will not stop 
< doing despite all stats) will be even more dangerous. As for
pedestrians, < even a small conversation with a friend will be
impossible while crossing < the road.

That's definitely the intuitive argument, but the counterintuitive
argument is that people do these distracting things because they have a
false sense of security.  The more dangerous the situation appears, the
less comfortable people feel and the more they pay attention.  An
utterly ridiculously extreme example: how many people would talk on
their cell phones driving down a road they new was littered with land
mines?  But even if people stay on their cell phones, there are many
other behaviors that are just as distracting or even worse.  If
Monderman's intersections lead people to pause in their conversation
with their passenger for a moment or to wait a few more seconds before
taking a sip of that $4 coffee they just picked up, then that will add
quite a bit of added safety.

> 3. No dividers between roads and sidewalks? Where do people stand if
they 
> want to ask for directions or kiss someone goodbye before crossing? Or
is 
> that not allowed?

By taking away the curb, you do take away a definitive boundary that
drivers and pedestrians can usually rely on.  But once again, you gain
an additional level of attention on everyone's part because of the
greater appearance of danger.  Which one has more of an effect?
Intuition would say the curb.  The results of Monderman's studies say
the appearance of danger.

Now granted, there may very well be some critical mass at which point
his theories don't hold up.  I remember that he did some studies at
rather busy intersections, but I'm pretty sure he never tried it in
downtown Manhattan.  But the fact is in the studies he performed, there
were significant improvements both in lowering the average time to drive
through and in lowering the number of accidents (usually to zero).
Maybe he's a total quack and made up all the numbers, but most likely
not.  I think it would be unwise to dismiss it just because it doesn't
match our intuition.  A lot of things don't match our intuition...been
to the edge of our flat world lately?

Matthew deStwolinski