Bifurcation structure of the Eckalbar stock-holding model

摘要

The inventory model proposed by Eckalbar, to account for historical stock fluctuations, oscillates under only some of the conditions claimed. It is also structurally unstable, though the central result that a change in inventory policy can induce oscillation is robust. We correct the analysis of the conditions for sustained oscillation, discuss the dynamical effects of the constraint that no variable becomes negative, and analyse a typical perturbation by which the onset of oscillation changes character.