  In this paper we propose a geometric approach to the selection of the equi-
librium price. After a perturbation of the parameters, the new price is
selected thorough the composition of two maps: the projection on the
linearization of the equilibrium man- ifold, a method that underlies
econometric modeling, and the exponential map, that associates a tangent vector
with a geodesic on the manifold. As a corollary of our main result, we prove
the equivalence between zero curvature and uniqueness of equilibrium in the
case of an arbitrary number of goods and two consumers, thus extending the
previous result by [6].
