Michael Mauboussin on Valuation, Base Rates and Expectations Investing

Successful long-term investing requires distinguishing between fundamental business ownership and market speculation. The "expectations investing" framework provides a rigorous approach by reverse-engineering current stock prices to identify the specific performance drivers—such as sales growth and margins—that the market assumes. This process shifts focus from simple valuation multiples, which often act as economic cul-de-sacs, to explicit cash flow projections. Modern markets increasingly rely on intangible assets like software and branding, which traditional accounting often misrepresents as expenses rather than investments. Furthermore, the "paradox of skill" suggests that as the absolute level of professional expertise increases, relative performance differences narrow, making alpha harder to achieve. Investors improve decision-making by applying base rates—analyzing historical reference classes—to ground their forecasts in reality rather than relying on subjective, narrow projections.