Copyright George Christos 2003
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number plates why so many characters and digits?
Recently I saw a car go through a red light, and none of us were able to get his number plate. We all looked at each other in amazement that this person was able to get away with this. Thinking about it later, I realised that I was unable to get his number because there is now an extra ‘1’ placed in front of the traditional number plate. Using 7 characters instead of 6 means the characters have to be smaller to fit onto the same sized number plate, making it harder to see. There’s another problem. The human brain has the natural capacity to remember 7±2 items in short-term memory. Ah, you say, but the number ‘1’ is redundant, so really there are only 6 characters to remember. The problem is that you can’t help looking at the redundant ‘1’ as you read from left to right.
Anyhow, why have we gone to 7 characters? This is where I am confused. With 4 digits and 3 letters there are about 180 million combinations possible, which can cater for over 100 cars each for every man, woman, and child in WA. The current licensing system has been around for 2 or 3 years now, and we have only just gone from using licence numbers beginning with 1A to licence numbers beginning with 1B. This means that we should get to 1Z in about 50 to 70 years time, and to 9Z in about 500 to 700 years. A licence plate with 3 letters and 3 numbers would generate about 18 million combinations (plenty), 2 letters and 4 digits would generate 6.76 million combinations. We may even be able to get away with as little as 2 letters and 3 digits (676,000 combinations) if we were to colour-code the plates each year. Using names may also be a good idea, as then people can remember them as a whole, as opposed to individual unrelated characters.
It would also make much more sense to put redundant characters like 1A at the end of the license plates so that drivers could get the most important digits of a license plate that distinguishes a vehicle.
phone numbers did we really need the '9' in front?
article in the West Australian, author G.A. Christos, October 2002
today tonight, channel seven television, August 2002
A few years ago the Australian Communication Authority deemed that we were running out of phone numbers and a 9 was placed in front of our telephone numbers. I would like to question whether this was really necessary and if it this was the best solution.
With 8 digits, we now have 100 million combinations of telephone numbers, which could cater for nearly 100 telephones for every business and household in Western Australia. Incidentally, New York still has only 7 digit phone numbers, with a slightly longer area code (which is easy to remember, or can be looked up). Why does Perth need so many digits?
I am also a bit confused as to why the extra 9 was added to the front of our phone numbers. It would have made more sense to place the 9 at the end of the phone numbers. Previously the first few digits gave us an indication of the area. If we were to place the 9 at the end of the old phone numbers, this would have stayed the case and it would have freed up 10 times the available numbers for each exchange. The Bassendean Exchange for example could have kept the prefixes 279 and 378 with 200,000 lines available, or if we were to use 279 only, this would have still had 100,000 lines. With the new system the following prefixes are used by the Bassendean Exchange: 9377, 9378, 9379, 9279, 6278, and 67282, allowing for 51,000 lines. If we stuck the 9 at the end, we could also eventually turn the 279 prefix into an area code and then we could get away with only 5-digit telephone numbers.
today tonight, channel seven television, August 2002mobile phones while driving and speed camera should be banned and limited respectively
with a Serial Mind
by George Christos
The brain is a truly amazing organ.
This piece of jelly-like material, which would fall apart if it was taken
out of our skulls, is responsible for our abilities to move, see, hear, smell,
feel, perceive, react, experience emotions, remember, think, plan, communicate
(orally and through the written word), and to act in a social and responsible
manner. The brain processes all of
these things, and much more, simultaneously. The reason it can do this is because it is wired and works in
parallel. This is quite different
to how a conventional computer works. A
computer can only process a single instruction at a time, one after the other.
It is said to be serial.
Although the brain can simultaneously process
multiple channels of information, not all of what it does enters conscious
awareness, and that which does reach consciousness is in competition with other
processes vying to enter consciousness.
It may surprise you to know that your conscious
awareness is serial. For starters,
you are only aware of a single channel of information processing at any one
moment, and then (surprise again) only of a small portion of any particular
channel. For example, you can
attentively look at something, listen to something, or think about something,
but only one thing at a time. And
when you look at something for example you can only focus your attention on a
very small part of your entire visual field.
Try the following experiment.
Focus on a letter (or word) on this page. Note how the other letters just a few inches away are out of
focus. Now move your attention to
one of these other nearby letters. As
you bring this letter into focus (or attend to it), you will notice that the
original letter you had focused on has now moved out of focus, or out of your
attention. If you swap your
attention back to the original letter, the second letter you just attended to
moves out of focus. (It actually
turns out that your visual attention is restricted to a small cone the size of a
5-cent coin held at arm's length.) [Incidentally,
this is one of the reasons why a photograph, which captures only a small part
your potential visual field, looks appealing - you can only attend to small part
of the photograph at any one moment.]
The same thing happens when you are listening
to someone. Other voices around you
are muffled until you divert your attention to one of them, but then the
original voice will move out of your attentive focus.
And if you think about something, both your visual and auditory awareness
diminishes for that precise moment.
The brain shares its experiences with us
through a serial attentive mechanism. [A
deeper issue that will not be addressed here is to explain 'us' or the self we
imagine to be within each of us.] All
of our senses and aspects within these senses are competing for this attention,
and the winner takes all.
Admittedly we can swap our attention from one
thing to another quite readily (this is called multi-tasking) and some functions
can proceed in an automated unconscious manner (like walking and eating), but
when our attention is concentrated on something everything else is out of
[Incidentally, females often claim they can
think about more than one thing at a time, whereas males cannot.
What this really means is that they multi-task more than men, or in other
words, their minds wonder a lot more. They
often think about psychological issues (why he did that, or she said that) and
other important matters, like shoes of course.
This wondering mind may also go someway towards explaining why they are
generally worse drivers than men (see below).
Seriously though, this knowledge about the
serial nature of the conscious mind has serious implications for driving a motor
vehicle, with using a mobile phone while driving, and with the excessive use of
speed cameras, in policing speed limits.
When you are talking to someone on a mobile
phone you are diverting your attention and taking it off your attention to
driving. It really does not matter
if you are using a hands-free kit or not. Recent
studies in New Zealand and Sydney have confirmed that it is just as dangerous to
use a hands-free kit as it is to actually hold the phone in your hand and talk.
This is no surprise to those who know how consciousness works in the
brain. When you are using a mobile
phone, you are listening, thinking and talking to the person on the other end of
the phone, and these neural activities interfere with the visual and cognitive
attention required for driving a car.
The devoted mobile-phone user may say that they
can quickly divert their attention to driving even if they are talking on a
phone, when they have to. This may
be true, but what people need to also realize is that driving a motor vehicle is
not just about observing and reacting. Driving
is a complicated business. One is
maneuvering an object weighing around one tonne at speeds in excess of 16 meters
per second (or 60 km/hr) in narrow and complicated thoroughfares with lots of
other people doing the same thing. This
task requires an enormous amount of conscious attention, in addition to the
constant need to make decisions, and anticipate events that may arise, while you
have to worry about what other drivers and pedestrians are doing and thinking.
[Oh, and by the way, this is all accomplished by that marvelous piece of
jelly-like material in your head.]
A good driver should be making judgements about
what other vehicles are doing (such as why did that car change lanes?),
anticipating events before they happen, and planning ahead.
These important thinking processes are also affected when one uses a
mobile phone, although I would have to admit that a lot of drivers do not
exercise any of these attributes when they are driving in any case.
Based on this, I believe that we should totally
ban the use of mobile phones in motor vehicles, whether or not they are fitted
with a hands-free device.
If you stop and think about it, attention loss
is probably the main cause of traffic accidents.
When we are intoxicated with alcohol, what suffers is your awareness (in
addition to your ability to react of course).
Fatigue is a major issue in road safety because it directly influences
attention. And why is it that there
are more accidents at intersections fitted with traffic lights?
This is because we tend to relax our driving attention as we approach
intersections fitted with traffic lights, and hence divert it to other things.
Maybe we are also paying too much attention to the traffic lights
themselves, worrying if they will suddenly change on us.
Have you ever noticed how capable people act when driving through an
intersection where the traffic lights have gone out.
This is because they have to heighten their attentive mechanisms to the
task of driving. And, just ask
yourself this. How many times have
you nearly had an accident because your attention was distracted while you were
looking at something on the side of the road, a grand old building, the
beautiful scenery, or a girl in a mini skirt, or just thinking about something?
If attention is such a key issue in road safety
we should also note that driving while you are talking to other people in the
car, or listening too intently to the radio can also be dangerous activities.
I really don't know what we can do about people who suffer from ADDD -
attention deficit driving disorder. And
there are people who just don't project ahead and anticipate what is happening
on the road.
People who use mobile phones while they drive
may hate me for what I have said, not that I really care, but to balance things
up a bit, let me say something they will welcome about speed cameras.
Most motorists are terrified about getting
caught speeding, so much so that they are constantly diverting their attention
to looking at the verge on the left-hand side of the road for speed cameras, and
at their speedometer. By diverting
so much of their attention to how fast they are going and whether there are
speed cameras ahead of them, they are taking their (serial) attention off the
task of driving.
This may also explain why it is that with all
the police attention on speeding and reducing speed limits that the road toll
has not really gone down at all. The
positive aspects of driving at slower speeds (which I do not dispute) are
counteracted by the reduced attention we spend on driving, because we are too
busy looking out for cameras and worrying about how fast we are going.
One could say that (over enforcement of) speed limits kill.
They are serial killers - excuse the pun.
I can recall a few years ago, when my kids and
I went up to talk to an operator of a Multanova camera and he told us that they
did not send out infringement notices to motorist who were up to 14 km/hr over
the limit. In time, this tolerance
was reduced to 8 km/hr, but now the police do not even tolerate speeding in
excess of 4 km/hr. Why all this
I believe that a more lenient and reasonable
enforcement of the law in regard to speeding, and a reduction in the number of
cameras would result in fewer road fatalities.
Another factor that needs to be taken into
consideration in all of this is that there is constant pressure on you to travel
as close as possible to the speed limit, perhaps even a little over the limit. If you don't you will find cars running up behind you.
And if you drive too slow, you will actually come in contact with more
vehicles. This increases the
likelihood of an accident. Slow drivers are just as much a traffic hazard as people who
drive too fast. The safest speed to
drive at is obviously whatever the other cars around you are doing.
That way you will not encounter as many vehicles on your journey.
The most ideal situation would be to allow traffic to flow in a more
self-organized manner, much like birds fly around without too much control.
I don't know how to do this - yet.
Another problem with reducing speed limits is
that you are generally on the road for longer periods of time as you go from A
to B to Z, and this also increases the probability you may be involved in an
Dr George Christos is a brain theorist working at Curtin University of Technology, and author of a recent book on the human brain called Memory and Dreams: The Creative Human Mind, currently only available in Australia at New Edition Bookshop in Fremantle.
Sunday Times, 22 June 2003
Sunday Times, 22 June 2003
West Australian 5 July 2003