qgames-7-threep2.txt

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A Nash equilibrium strategy for this game is ULA.
Looking at the payoff element for ULA
we see that AB has no incentive to switch to B,
LR has no incentive to switch to R,
and UD has no incentive to switch to D.
There is one thing unusual about this,
however, which is that it is vulnerable to a coalition move.
If LR and UD were to conspire with each other,
then they would be able to force DRA to become an equilibrium.
Note that starting from DRA, if AB were to switch to B, then
LR and UD could perform a sequence of moves which would
propel the system back to DRA.
This emphasizes the fact that Nash equilibria are only
unilaterally optimal.