Endogenous growth and wealth inequality under incomplete markets and idiosyncratic risk

This paper describes the equilibrium properties and dynamics of a model which combines the key features of the standard incomplete market model (Aiyagari, 1994) with a standard endogenous growth mechanism to gain a deeper understanding of the feedback effects between growth and wealth inequality in the presence of credit frictions and idiosyncratic risk. We characterize growth equilibria and find that a balanced growth path not necessarily exists if households are subject to ad hoc borrowing constraints. Growth, inequality, and risk are positively related in our model, but we also identify a hump-shaped relationship between welfare and risk, indicating a tradeoff relationship between risk-pooling and growth in the determination of welfare. The growth rate responds to changes in the wealth distribution and displays transitional dynamics towards the balanced growth path.