MARCH 2020


Honestly. Are the blokes who set up our traffic lights trying to save lives or just increase revenue?

Very occasionally they do the right thing. Like the pedestrian intersection at the "T" intersection of Oxford St, Bronte Rd & Grosvenor St in Bondi Junction.  What happens is all the traffic lights are red and all the pedestrian crossings are green. And when the pedestrians get an "amber" light, it is a countdown to zero of when the road traffic gets a green light.  That countdown is a brilliant idea, and they ought to patent it and put it everywhere.  In addition, I would suggest that they should apply the same technology to warn cars when the lights turn from green to amber to red.  (They can patent that idea on my chit). Put the amber on countdown, so (if for instance a bus or truck had blocked our vision) we would know instantly how much time we had to stop, or whether to continue because the sudden braking required might get us a rear ender.

But mostly they get it wrong. A prime example is the T intersection of Darlinghurst Rd and Bayswater Rd in Kings Cross.  When they stop all road traffic, do they open all pedestrian crossings? No.  The Darlinghurst Rd crossings say "Walk" but the Bayeswater Rd crossing is "Don't Walk".  From there it gets worse.  Before the Darlinghurst Rd pedestrians can get more than halfway across, the Bayswater lights allow cars to go forward.  Which they do, tooting the pedestrians who were unable to cross and now have a flashing "Don't Walk".  The idea was probably to allow road traffic to get through rapidly.  But that is a busy pedestrian intersection, and not the place to save driver's time if they have to give way to pedestrians.

Other issues are "Don't Walk" signs switched on at times when traffic has a red light. (East side crossing at Devonshire/Bourke streets intersection, North side crossing on Bourke/Cleveland.)

And still other issues are the approximately three second pause between closure of a green light that allows left turn and through traffic and opening of a green left arrow.  That happens at the South Dowling/Oxford St intersection and at the New South Head/New Maclean Streets intersection.  Cars must brake to a stop, only to then have to accelerate left.

Why does this endanger lives?  I note that Pedestrians show contempt for the designers and the time that is consequently wasted. So they just break the law and cross at the "Don't Walk" signs.  And because the timing of amber lights varies, drivers are encouraged to "run" amber lights which makes accident's more likely.

But then, those traffic lights people think they are the gods. Raising revenue.  Probably get commended by the premier.

Hey Doris!  Get a citizen's committee or somesuch onto this. Making lights more efficient might reduce revenue, but will probably teach us respect for the traffic lights & save lives.


Diamond Princess, a cruise ship with COVID-19 was moored for 14 days in Japan.  Doctors were testing the passengers on board and produced the following data.  The data below was sourced from this paper.

AgeRange No. of passengers Symptomatic cases Asymptomic cases (%)
Total cases
(as % of passengers)
Observed deaths on cruise ship
0 - 9 16 0 1
1 (6%) 0
10 - 19 23 2 3
5 (21%)
20 - 29 347 25 3 28 (8%)
30 - 39 428 27 7 34 (8%)
40 - 49 334 19 8 27 (8%)
50 - 59 398 28 31 59 (15%)
60 - 69 923 76 101 177 (19%)
70 - 79 1015 95 139 244 (24%)
80 - 89 216 29 25 54 (25%)
Totals 3711 301 318 619 (17%)

Things to notice.
  • Most (2154 out of 3711) passengers were over 60.
  • More than half the patients aged over 50 were "asymptomatic".

I hypothesize the following:

  • That the "asymptomatic" cases might have resulted from a very low dose infection rate, whereas the symptomatic cases resulted from a high dose infection.  This hypothesis could be tested by determining whether the later asymptomatic cases came from cabins that were not shared with symptomatic cases.

  • That the progress (eg seriousness) of the disease is related to the individual's "activity level".  Small children and young adults have high activity levels and tend to not get very sick. Older people tend to be more sedentary and have the highest proportion of deaths.  This hypothesis could be tested against observed activity levels.

  • Because asymptomatic cases are thought to be spreaders, it is not going to be easy to eradicate this disease without everyone being diagnosed repeatedly.  Having an effective self diagnosis kit is probably a good way to do that. Which kits are in short supply.