Bernardo A. Huberman and Natalie S. Glance
Dynamics of Computation Group
Xerox Palo Alto Research Center
Palo Alto, CA 94304
huberman@parc.xerox.com
We elucidate the dynamics of ongoing collective action among
intentional agents with diverse beliefs and imperfect information.
Their decisions on whether or not to contribute to the collective
good depend not only on the past but also on their expectations as
to how their actions will affect those of others. We show that in
attempts at collective action the onset of overall cooperation can
take place in a sudden and unexpected way. Likewise, defection can
appear out of nowhere in very large, previously cooperating groups.
These outbreaks mark the end of long transient states in which defection
or cooperation persists in groups that cannot sustain it indefinitely.
Diversity of beliefs among individuals acts as an additional source
of uncertainty and instigates the outbreaks.
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