Capital-labor substitution and competitive nonlinear endogenous business cycles

We develop in this paper simple geometrical methods to study local indeterminacy, bifurcations and stochastic (sunspot) equilibria near a steady state, in nonlinear two dimensional economic models. We present stochastic sunspot equilibria, which allows a constructive description of local bifurcations. The latter analysis is relevant when some eigenvalues of the linearized dynamics, near the steady state, have a modulus close to one (“unit root(s)”), as taking into account small nonlinearities generates linear local approximation. These methods are applied to a simple aggregative model (Woodford (JET, 1986)), to study in particular the influence of capital-labor substitution and of the aggregate labor supply wage elasticiy, on the occurrence of competitive endogenous deterministic or stochastic fluctuations.