Module 3: The Factor Revolution - Fama-French & Smart Beta

CAPM assumes that Market Risk (Beta) is the only factor driving returns. In 1992, Eugene Fama and Kenneth French shattered this assumption, proving that other structural "Factors" consistently generate excess returns. This birthed the modern era of Quantitative Factor Investing (Smart Beta).

1. The Fama-French Three-Factor Model

Fama and French proved that over long time horizons in the US market, two specific types of stocks consistently outperform the broader S&P 500:

• Size Factor (SMB - Small Minus Big): Small-cap companies historically outperform massive blue-chip companies due to higher runway for growth and higher embedded risk.
• Value Factor (HML - High Minus Low): Value stocks (high book-to-market ratios) structurally outperform expensive Growth stocks.

2. The Expansion of Factors

Modern institutional quants have expanded the model to include additional persistent anomalies:

• Momentum: Stocks that have gone up recently tend to keep going up; stocks that have crashed tend to keep crashing.
• Quality: Companies with robust balance sheets, low debt, and stable cash flows outperform highly leveraged, erratic companies over the economic cycle.

Case Study: AQR Capital Management AQR Capital Management, a premier US quantitative hedge fund, is built entirely upon factor investing.

• Analysis: Instead of hiring analysts to read 10-Ks and interview CEOs, AQR algorithms scan the entire US equity market, aggressively buying stocks that exhibit a confluence of Value, Quality, and Momentum factors, while shorting stocks that lack them. This systemic, emotionless approach eliminates behavioral biases and captures the mathematical drift of the market factors over time.

Self-Assessment Quiz

1. Contrast the original CAPM model with the Fama-French Three-Factor Model.
2. Define the "Momentum" factor in quantitative portfolio management.