Financial Theory

Yale, , Prof. John Geanakoplos

Updated On 02 Feb, 19


Why Finance? - Utilities, Endowments, and Equilibrium - Computing Equilibrium - Efficiency, Assets, and Time - Present Value Prices and the Real Rate of Interest - Irving Fisher's Impatience Theory of Interest - Shakespeare's Merchant of Venice and Collateral, Present Value and the Vocabulary of Finance - How a Long-Lived Institution Figures an Annual Budget. Yield - Yield Curve Arbitrage - Dynamic Present Value - Social Security - Overlapping Generations Models of the Economy - Demography and Asset Pricing: Will the Stock Market Decline when the Baby Boomers Retire? - Quantifying Uncertainty and Risk - Uncertainty and the Rational Expectations Hypothesis - Backward Induction and Optimal Stopping Times - Callable Bonds and the Mortgage Prepayment Option - Modeling Mortgage Prepayments and Valuing Mortgages - History of the Mortgage Market: A Personal Narrative - Dynamic Hedging - Dynamic Hedging and Average Life - Risk Aversion and the Capital Asset Pricing Theorem - The Mutual Fund Theorem and Covariance Pricing Theorems - Risk, Return, and Social Security - The Leverage Cycle and the Subprime Mortgage Crisis - The Leverage Cycle and Crashes


Lecture 5: Present Value Prices and the Real Rate of Interest

4.1 ( 11 )

Lecture Details

Financial Theory (ECON 251)

Philosophers and theologians have railed against interest for thousands of years. But that is because they didnt understand what causes interest. Irving Fisher built a model of financial equilibrium on top of general equilibrium (GE) by introducing time and assets into the GE model. He saw that trade between apples today and apples next year is completely analogous to trade between apples and oranges today. Similarly he saw that in a world without uncertainty, assets like stocks and bonds are significant only for the dividends they pay in the future, just like an endowment of multiple goods. With these insights Fisher was able to show that he could solve his model of financial equilibrium for interest rates, present value prices, asset prices, and allocations with precisely the same techniques we used to solve for general equilibrium. He concluded that the real rate of interest is a relative price, and just like any other relative price, is determined by market participants preferences and endowments, an insight that runs counter to the intuitions held by philosophers throughout much of human history. His theory did not explain the nominal rate of interest or inflation, but only their ratio.

Complete course materials are available at the Open Yale Courses website httpopen.yale.educourses

This course was recorded in Fall 2009.



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Excellent course helped me understand topic that i couldn't while attendinfg my college.

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Great course. Thank you very much.