Community Issues

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.


article in the West Australian, author G.A. Christos, October 2002

today tonight, channel seven television, August 2002


phone numbers did we really need the '9' in front?

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 2002 

mobile phones while driving and speed camera  should be banned and limited respectively

Driving with a Serial Mind

by George Christos

(revised June 2003) 

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 conscious focus. 

[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 obsession?

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 accident.

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

West Australian 5 July 2003