Innovation, cycles and growth

The purpose of this paper is to present a model of growth with endogenous fluctuations. The main feature of our model is that it throws light on the relationships between long waves and business cycles in the economy. The driving forces in the model work in this way: endogenous R&D investment creates new cumulative knowledge. When this knowledge reaches a threshold H*, radical innovations occur which generate productivity growth via the substitution of old capital with new capital. These disruptive events appear recurrently, generating long waves and revitalizing the growth process. Short-term cycles in the model come from the interactions between these innovation-driven transformations and certain prey-predator mechanisms that involve the labor market. We find that our model presents excellent properties: the model generates endogenous cyclical growth as a disequilibrium process; persistent and irregular short cycles appear interwoven with the long waves; and there is a strong significant interaction between both kinds of fluctuations.