Professor Brad Cornell: A Skeptic's Look at the Cross Section of Expected Returns (EP.151)

Episode Summary

Executive Summary: Professor Brad Cornell challenges factor investing orthodoxy on the Rational Reminder Podcast, arguing that financial economics is non-stationary and that most empirical regularities like the value premium are unreliable. He advocates for fundamental DCF analysis over characteristic-based strategies, critiques ESG investing as poorly defined and potentially misleading, and warns that the implied equity risk premium is currently low (~4%), suggesting lower future returns. His skeptical perspective emphasizes that markets are inherently unpredictable and that past performance is a poor guide for future returns.

Main Topics: Non-stationarity in Financial Markets (Priority: 5/5): Cornell argues that financial markets are non-stationary, meaning the underlying processes change over time. This undermines the reliability of historical empirical regularities (e.g., value premium) and most cross-sectional expected return models. Critique of Factor Investing and Characteristics (Priority: 4/5): Cornell distinguishes between risk factor loadings and stock characteristics, questioning the validity of characteristic-based premiums and arguing that many apparent factors may be spurious due to non-stationarity and data mining. Big Market Delusion and Competition (Priority: 4/5): Focuses on how sectors with enormous growth potential (e.g., electric vehicles, AI) attract investor sentiment and narratives, leading to overpriced valuations. Cornell highlights the role of competition and the likelihood that only few winners emerge, while most firms fail. Fund Manager Selection and Past Performance (Priority: 4/5): Cornell presents evidence that picking fund managers with strong past performance is a poor strategy; instead, past losers tend to outperform winners on average due to mean reversion. He advocates evaluating a manager's investment theory rather than historical returns. Equity Risk Premium Estimation (Priority: 3/5): Cornell recommends using Damodaran's implied equity risk premium (~4% over Treasuries currently) for financial planning, warning that traditional historical averages (e.g., 6%) are unrealistic and that low premiums imply lower future returns. ESG Investing: Definitions and Market Equilibrium (Priority: 3/5): Cornell critiques ESG as poorly defined and often based on narratives. He explains that during a transition period, ESG stocks may appreciate due to falling cost of capital, but future expected returns are correspondingly lower, which many investors overlook.

Key Arguments: Financial markets are non-stationary, making historical empirical regularities (e.g., value premium) unreliable for predicting future returns. Factor investing confuses stock characteristics with risk factors; the true approach to value is price-to-value via DCF, not price-to-book or price-to-earnings. Sectors like electric vehicles suffer from 'big market delusion': narratives drive prices unsustainably, ignoring competitive dynamics and long-run winners. Past fund manager performance is inversely predictive; losers tend to outperform winners due to mean reversion in the underlying strategies. The implied equity risk premium (~4% for US equities) is low today, meaning investors should lower return expectations for the next decade. ESG investing often imposes a lower cost of capital on green firms, but that implies lower expected returns going forward, contrary to common investor beliefs.

Data Points: Implied equity risk premium (US equities): ~4% over Treasuries - As of the recording, based on Damodaran's calculations; implies total stock return of about 5.5%. Value premium timeline: Disappeared and reversed around 2008 - After being a consistent empirical regularity for decades, the value effect vanished post-2008, illustrating non-stationarity. Tesla target price per DCF: ~$300 - Cornell and Damodaran's estimate assumes Porsche-like margins and Toyota-like output; equates to ~1.5% equity risk premium. Tesla's implied equity risk premium: ~1.5% - Extremely low discount rate rationalizing current price; contrasts with market's 4% ERP. SPAC examples: N/A - Cornell notes SPAC issuers exploit mispricing in sectors like EVs, green energy, and AI. Historical vs. current expected returns: Historical ERP ~6%; current implied ~4% - Pension funds often use 7% portfolio return, but Cornell argues 4.5% is more realistic.

Pivotal Quotes: "If the world is primarily non-stationary, most of it's not going to work long run." — Brad Cornell: Commenting on the reliability of cross-sectional expected return models and factor investing. "The winners are winners because their strategy happened to work in the past... to the extent that the market's a little bit mean reverting... the losing managers do better, and the Kathy Woods do worse." — Brad Cornell: Explaining why past fund performance is inversely predictive; losers tend to outperform winners. "I don't think value investing is dead, but it should be interpreted properly. It's price to value. And value should be your estimate of value, not something like price to book or price to earnings." — Brad Cornell: Distinguishing between traditional characteristic-based value investing and fundamental DCF-based value investing.

Implications: Investors should lower return expectations, use implied ERP (~4%) for planning, focus on DCF valuations over factor exposures, be skeptical of past fund performance, and critically evaluate ESG claims. This calls for humility about market predictability and a disciplined, fundamental approach.