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Efficient Markets vs Excess Volatility

By Robert Shiller - Yale
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Lecture Description

Several theories in finance relate to stock price analysis and prediction. The efficient markets hypothesis states that stock prices for publicly-traded companies reflect all available information. Prices adjust to new information instantaneously, so it is impossible to "beat the market." Furthermore, the random walk theory asserts that changes in stock prices arise only from unanticipated new information, and so it is impossible to predict the direction of stock prices. Using statistical tools, we can attempt to test the hypotheses and to predict future stock prices. These tests show that efficient markets theory is a half-truth: it is difficult but not impossible for some people to beat the market.

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Course Index

  1. Finance and Insurance as Powerful Forces in Our Economy and Society
  2. Review of Probability and Statistics; Intro to Present Value
  3. Technology and Invention in Finance
  4. Portfolio Diversification and Supporting Financial Institutions (CAPM Model)
  5. Insurance: The Archetypal Risk Management Institution
  6. Efficient Markets vs Excess Volatility
  7. Behavioral Finance: The Role of Psychology
  8. Human Foibles, Fraud, Manipulation, and Regulation
  9. Investing for the Long Run
  10. Debt Markets: Term Structure
  11. Stocks
  12. Real Estate Finance and Its Vulnerability to Crisis
  13. Banking: Successes and Failures
  14. The Efficiency of Markets
  15. Guest Lecture by Carl Icahn
  16. The Evolution and Perfection of Monetary Policy
  17. Investment Banking and Secondary Markets
  18. Professional Money Managers and Their Influence
  19. Brokerage, ECNs, etc
  20. Private Equity and the Financial Crisis
  21. Forwards and Futures
  22. Stock Index, Oil and Other Futures Markets
  23. Options Markets
  24. The Democratization of Finance
  25. Learning from and Responding to Financial Crisis, Part I
  26. Learning from and Responding to Financial Crisis, Part II