InfoCoBuild

ECON 251: Financial Theory

Lecture 16 - Backward Induction and Optimal Stopping Times. In the first part of the lecture we wrap up the previous discussion of implied default probabilities, showing how to calculate them quickly by using the same duality trick we used to compute forward interest rates, and showing how to interpret them as spreads in the forward rates. The main part of the lecture focuses on the powerful tool of backward induction, once used in the early 1900s by the mathematician Zermelo to prove the existence of an optimal strategy in chess. We explore its application in a series of optimal stopping problems, starting with examples quite distant from economics such as how to decide when it is time to stop dating and get married. In each case we find that the option to continue is surprisingly valuable. (from oyc.yale.edu)

Lecture 16 - Backward Induction and Optimal Stopping Times

Time Lecture Chapters
[00:00:00] 1. Calculating Default Probabilities
[00:14:58] 2. Relationship between Defaults and Forward Rates
[00:28:09] 3. Zermelo, Chess, and Backward Induction
[00:36:48] 4. Optimal Stopping Games and Backward Induction
[01:06:47] 5. The Optimal Marriage Problem

References
Lecture 16 - Backward Induction and Optimal Stopping Times
Instructor: Professor John Geanakoplos. Transcript [html]. Audio [mp3]. Download Video [mov].

Go to the Course Home or watch other lectures:

Lecture 01 - Why Finance?
Lecture 02 - Utilities, Endowments, and Equilibrium
Lecture 03 - Computing Equilibrium
Lecture 04 - Efficiency, Assets, and Time
Lecture 05 - Present Value Prices and the Real Rate of Interest
Lecture 06 - Irving Fisher's Impatience Theory of Interest
Lecture 07 - Shakespeare's Merchant of Venice and Collateral, Present Value and the Vocabulary of Finance
Lecture 08 - How a Long-Lived Institution Figures an Annual Budget; Yield
Lecture 09 - Yield Curve Arbitrage
Lecture 10 - Dynamic Present Value
Lecture 11 - Social Security
Lecture 12 - Overlapping Generations Models of the Economy
Lecture 13 - Demography and Asset Pricing: Will the Stock Market Decline when the Baby Boomers Retire?
Lecture 14 - Quantifying Uncertainty and Risk
Lecture 15 - Uncertainty and the Rational Expectations Hypothesis
Lecture 16 - Backward Induction and Optimal Stopping Times
Lecture 17 - Callable Bonds and the Mortgage Prepayment Option
Lecture 18 - Modeling Mortgage Prepayments and Valuing Mortgages
Lecture 19 - History of the Mortgage Market: A Personal Narrative
Lecture 20 - Dynamic Hedging
Lecture 21 - Dynamic Hedging and Average Life
Lecture 22 - Risk Aversion and the Capital Asset Pricing Theorem
Lecture 23 - The Mutual Fund Theorem and Covariance Pricing Theorems
Lecture 24 - Risk, Return, and Social Security
Lecture 25 - The Leverage Cycle and the Subprime Mortgage Crisis
Lecture 26 - The Leverage Cycle and Crashes