  We explore the effect of discounting and experimentation in a simple model of
interacting adaptive agents. Agents belong to either of two types and each has
to decide whether to participate a game or not, the game being profitable when
there is an excess of players of the other type. We find the emergence of large
fluctuations as a result of the onset of a dynamical instability which may
arise discontinuously (increasing the discount factor) or continuously
(decreasing the experimentation rate). The phase diagram is characterized in
detail and noise amplification close to a bifurcation point is identified as
the physical mechanism behind the instability.
