The sophistication of financial decisions varies with age: middle-aged adults borrow at lower interest rates and pay fewer fees compared to both younger and older adults. We document this pattern in ten financial markets. The measured effects cannot be explained by observed risk characteristics....

This paper develops a model of the credit market where the equilibrium lending mechanism, as well as the economy's aggregate investment and output, are endogenously determined. It focuses on two crucial elements. One is the micro theory of optimal lending mechanism. Instead of imposing a...