Masters in Business: Yale Professor Robert Shiller (Audio)

Episode Summary

Executive Summary: Barry Ritholtz interviews Nobel laureate Robert Shiller on behavioral finance, market bubbles, and risk management. Shiller explains why investor psychology, crowd behavior, and overconfidence drive booms and busts, discusses the Case-Shiller index and CAPE valuation model, and argues that markets are only partly efficient. He also explores technology, inequality, and new financial products for managing life and income risks.

Main Topics: Behavioral finance and crowd psychology (Priority: 5/5): Shiller describes how psychology, fashions, peer pressure, cognitive dissonance, and rationalization shape investor behavior and help explain bubbles and crashes. Market efficiency vs. inefficiency (Priority: 5/5): He presents efficient markets as a useful half-truth: prices often reflect news, but sometimes drift far from fundamentals due to human behavior. Housing bubbles and the Case-Shiller index (Priority: 5/5): Shiller explains the creation of a repeat-sales housing price index and how surveys and valuation ratios helped him identify the 2003-2006 housing bubble. Valuation and the CAPE ratio (Priority: 5/5): He details the cyclically adjusted PE ratio as a tool for estimating long-run stock returns and argues that valuation matters for expected returns. Portfolio construction and risk management (Priority: 4/5): Shiller recommends broad diversification, passive investing for most people, and more advanced financial products to insure against housing and income shocks. Technology, automation, and inequality (Priority: 4/5): The discussion expands to driverless taxis, biotechnology, and the possibility that technology will disrupt jobs and widen inequality unless society plans ahead. Global development and emerging markets (Priority: 3/5): Shiller reflects on India, China, and the Pacific Rim, arguing that development requires tailored institutional and social solutions rather than one-size-fits-all economics.

Key Arguments: Investor behavior is strongly shaped by psychology, not just information, which is why markets can overshoot and crash. Efficient market theory explains some price movements, but not all; it is a half-truth rather than a complete model. Questionnaire surveys can reveal irrational expectations that standard market models miss, as shown in his housing bubble work. Housing is often treated like a great investment, but over long periods real home prices were roughly flat while carrying costs matter. The CAPE ratio improves on standard P/E by averaging earnings over 10 years, making it useful for forecasting long-run returns. Most investors should use diversified, low-cost indexing, while sophisticated professionals can occasionally outperform with great effort. Finance should be understood primarily as risk management: spreading uncertainty across investors enables innovation and economic progress. Future financial products could insure home values and income streams, helping people cope with technology-driven volatility and inequality.

Data Points: Yale teaching tenure: 32 years - Schiller says he has taught economics at Yale for 32 years. Housing price decline: 33% - Ritholtz cites the national housing price drop after the bubble. Black Monday drop: 23% in one day - October 19, 1987, used as an example of market irrationality. Housing expectations survey: About 10% per year for 10 years - Homebuyers in 2003 expected very high home-price appreciation. Real home prices, 1890-1990: Almost no change - Schiller notes that inflation-adjusted home prices were flat for a century. CAPE average level: 15-16 - Schiller says this is the historical average range for CAPE. CAPE level discussed: Around 25-26 - He describes the market as pricey but not extreme in that range. Expected real equity returns: 3% to 4% - Schiller says CAPE suggests this approximate real return over the next 10 years. S&P 500 peak-to-recovery: 13 years - Ritholtz notes the index did not reclaim its 2000 peak until 13 years later. S&P 500 level at 2000 peak: 1500 - Referenced when discussing the dot-com era valuation peak. S&P 500 level after 2009 bottom: 666 to about 2000 - Used to illustrate the long post-crisis rally. NASDAQ move during dot-com peak: 2500 to 5000, then to 1100 - Ritholtz cites the boom-bust trajectory around 1999-2000. NASDAQ P/E ratio at peak: Over 100 - Used to show extreme dot-com valuations. S&P 500 CAPE at 2000 peak: In the 40s - Ritholtz references the cyclically adjusted valuation extreme. Passive indexing industry size: About $3 trillion, with $2 trillion passive - Ritholtz cites Vanguard as an example of passive investing's growth. Course enrollment: Close to 40,000 students - Schiller discusses his Coursera finance course. Course completion example: 8,000 graduated; 350 failed - He describes results from a prior online course run. Probabilities of venture success: 20% - Schiller uses venture capital as an example of risk spreading. India household plumbing: 50% lacking toilets and indoor plumbing - He cites this as an example of uneven development.

Pivotal Quotes: "The theory actually has some value. It's a half-truth." — Robert Schiller: His assessment of efficient market theory during the discussion of booms and busts. "The future is unknowable. There are risks inherent to that. It's our responsibility to manage those risks." — Robert Schiller: On finance as risk management rather than simple return chasing. "If you do what everyone else does in investing, you'll just have the market return." — Robert Schiller: On the dangers of crowd behavior and the limits of imitation in markets.

Implications: Listeners should treat markets as partly psychological and focus on diversification, discipline, and risk management. For investors, valuation still matters over long horizons; for policymakers, technology-driven inequality may require new insurance and social-policy tools.