Fixed Capital, Composite Form of Technological Progress, and Goodwin Cycle

In this study, we develop a Goodwin model of the composite form of technological progress under the balance of payments constraint. Subsequently, we describe the inherent periodicity of fixed capital investment and verify the rationality of using finite order Fourier series to describe the fixed capital investment function. On this basis, the fixed capital investment data of 10 representative countries are fitted with the finite order Fourier series. The goodness of fit is greater than 0.9, which verifies the feasibility of using finite order Fourier series to describe the fixed capital investment function. Finally, we introduce the finite order Fourier series form into the capital accumulation function of the Goodwin model. The study finds that the inherent periodic characteristics of fixed capital do not affect the overall cyclical trend derived from the Goodwin model. However, these characteristics affect the amplitude of local fluctuation and the relative position of the cycle