The core social grouping is the set of individuals from whom one would seek
personal advice or help in times of severe emotional and financial
distress.  Size typically 3 - 5 individuals.

Next is a group of nine to 15 people that characteristically consists of
all the individuals with whom one has special ties.  These people are
typically contacted at least one a month.

The ethnographic data on hunter-gatherer societies point to a grouping of
30 -  50 people as the size of overnight camps.

Science & Theology News, May, 2005, p 11

People Who experience mood swings, fear,
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