clusters

["Kjell A. Johansen" <kajohans@powercom.net>]

Radsafers,
The explanation for clusters was discussed by Joel Cehn in one of the
IAEA Bulletins back in the 1992-1995 time frame.  One of the experiments
Joel suggested was to take a large jar and fill it up with equal numbers
of black and white marbles.  Shake and you will see clusters of black
marbles.  It's just plain statistics and does not have to represent a
cause and effect relationship in the real world.  There also is the
study of cancer clusters around British military installations.  Some of
the clusters showed up around castles.  So much for cause and effect.

Kjell Johansen
kajohans@powercom.net

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