Do Ak models really lack transitional dynamics ?

Abstract

Contrary to a popular belief, the most popular Ak growth models display transitional dynamics once the representative agent and complete markets assumptions are overturned. The class of models is identified with diminishing-returns at individual but constant-returns at aggregate due to externality effects. Under incomplete markets, the former implies that dynasties with a lower levels of initial capital grow faster. This is picked up by the aggregate economy that passes through a long transitional period before it converges to its balanced growth path. During the transition period, aggregate consumption and output grow at the same rate but higher than that of capital.