A Model of Moderation: Finding Skiba Points on a Slippery Slope
journal contribution
posted on 2002-12-09, 00:00authored byJonathan P Caulkins, Gustav Feichtinger, Dieter Grass, Gernot Tragler
A simple model is considered that rewards ”moderation” - finding the
right balance between sliding down either of two ”slippery slopes”. Optimal
solutions are computed as a function of two key parameters: (1) the cost of
resisting the underlying uncontrolled dynamics and (2) the discount rate.
Analytical expressions are derived for bifurcation lines separating regions
where it is optimal to fight to stay balanced, to give in to the attraction
of the ”left” or the ”right”, or to decide based on one’s initial state. The
latter case includes situations both with and without so-called Dechert-
Nishimura-Skiba (DNS) points defining optimal solution strategies. The
model is unusual for having two DNS points in a one-state model, having
a single DNS point that bifurcates into two DNS points, and for the ability
to explicitly graph regions within which DNS points occur in the 2-D
parameter space. The latter helps give intuition and insight concerning
conditions under which these interesting points occur.