In a message dated 09/12/2008 00:32:46 GMT Standard Time,  [log in to unmask] 
writes:

calculate a value representing the overall
strength of a  colony.


Is strength your only criterion?  It seems to be a very narrow view,  but 
measurable.  Simply shake the bees (as if doing a Taranov swarm)  onto a sheet, 
tie the corners and hang it from a scale.  If done at  the appropriate season 
for your area you could then use the bees actually to  make a Taranov swarm, in 
which case you would need to re-weigh the swarm and do  some simple 
arithmetic, or else simply dump the all bees back in the hive you  took them from, 
maybe having given them a good dusting with sugar while out of  the hive.
 
Chris

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