S. Rao Aiyagari
In this article, I suggest that incomplete markets and transaction costs are crucial for explaining the high equity premium and the low risk-free rate. I first demonstrate the failure of the complete frictionless markets model in explaining these return puzzles and then show how introducing incomplete markets and transaction costs can lead to success. Additionally, I explain how these features lead to predictions concerning individual consumptions, wealths, portfolios, and asset market transactions that are in better agreement with the facts than the predictions of the complete frictionless markets model.
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