Does Joel Greenblatt’s “Magic Formula” Still Work?

In 2005, Joel Greenblatt published a book called The Little Book that Beats the Market. Its explicit aim was to “explain how to make money in terms that even my kids could understand (the ones already in sixth and eighth grades, anyway).” Although it used language and examples that were aimed at children, it was widely read by folks of all ages. The first five chapters, before Greenblatt gets into his investment strategy, comprise an excellent introduction to value investing. Clearly written, easy to understand, it’s principled and right.

A Stock-Picker’s Guide to Benjamin Graham’s Screening Rules

Benjamin Graham, who has often been called the father of value investing, published The Intelligent Investor in 1949 and revised it several times, most recently in 1972. In that last and fourth edition, published in 1973, he included three different sets of guidelines, which could be called “checklists” or “screens.” The first was for the “defensive investor,” and it’s the most famous. The second was a rule for investing in “Net-Current-Asset (or ‘Bargain’) Issues.” And the third was for the “enterprising investor.”

Change Partners: Some Thoughts on Market Regimes

A lot of investors talk about “market regimes.” This term can have several different meanings. Classically, a market regime is characterized primarily by four measures: interest rates, inflation, GDP growth, and unemployment; often added to these are characterizations of government fiscal and monetary policy. But one can also talk about a market regime in terms of which stock factors work and which don’t.

The Value Inversion

For the past few years, investors have noticed what we call a “value inversion,” which appears to be getting progressively worse. Theoretically—and normally—stocks with low price-to-sales ratios (cheap stocks) outperform those with high price-to-sales ratios (expensive stocks). Such was the case over the majority of the current century, and indeed, as James O’Shaughnessy has shown in What Works on Wall Street, for most of the twentieth century too.

A Tale of Two Volatilities

When we as investors talk about volatility, we’re usually talking about variability in price returns. If an investment goes up and down 5% to 10% per day, that’s high volatility; if it goes up and down 0.05% to 0.1% per day, that’s low volatility. It’s a relatively simple concept, and is traditionally measured using standard deviation.
But when we compare investments to each other, we start talking not only about variability in price returns, but also about beta. And the implicit assumption is that beta measures something very different from variability.