War & Poisson distribution

[huy.duong@ctsu.ox.ac.uk]

Dear anh Tuan,

Do you mean

           0.69^x\times e^{-0.69}/x!,

ie a Poisson dist with mean 0.69, instead of   

 P(X = x) = 0.60 x e**(-0.69) / x!?

If the wars occur at a fixed rate on average and independently and at random
then a Poisson distribution with a suitable mean is good.

Fixed rate on average? No. World population increases between 1500 and 1931
and it becomes easier to mobilise 50000+ men, so the rate of 50000+ man war
should increase. For 1500-1931 I don't think that this is cancelled out by 
people less likely to resort to war and by fighting war with smaller proportions
of the population. I think this is enough to say that the fit is a fluke
or a fiddle.

Independent? The wars in WWI were related, the Prussian wars were related, the 
Napoleonic wars were related, the Louis XIV wars were related, the Swedish wars 
were related, etc, wars by a powerful Ming or Ching emperor were related,
wars after the Japanese modernisation were related etc. But it is reasonable to 
think that in the old days in any one year clusters of related wars in different 
regions of the world are quite independent. But how reasonable?

Random. Quite reasonable.

Huy