Goodwin 1951 – Continuous Three-Regime Cycle

Strict continuous-time version of Goodwin’s simplest nonlinear accelerator: C(t)=αY(t)+β, Y(t)=C(t)+I(t), I(t)=K̇(t), Ξ(t)=a·t+κY(t), and K̇(t) ∈ {I*, 0, I**} depending on whether actual capital is below, equal to, or above desired capital.