A Note On Variable Capital Utilization In Growth And Business Cycle Theory

It was always considered to be a major achievement of modern business cycle economics that it was solidly grounded in neoclassical growth theory. Preserving this joint foundation, however, imposes a discipline on the specification of models with variable capital utilization. In this note we show that conventional specifications of the depreciation cost of capital utilization and the labor supply elasticity, introduced into business cycle theory to generate a satisfactory amplification of shocks, entail counterfactual growth dynamics: the positive association between capital stock and GDP along the growth path turns negative. Across economies with access to the same technology, the economy with the lowest capital stock per capita is predicted to produce the highest output per capita. We compute lower and upper bounds for the involved elasticities between which these counterfactual dynamics are avoided.