Abstract
Investors’ return expectations are pivotal in stock markets, but the reasoning behind these expectations is not well understood. This paper explores economic agents’ mental models of what drives returns. We survey the general population, retail investors, financial professionals, and academic experts to investigate how they forecast and explain future returns in scenarios with stale news about future company earnings. We find that investors strongly disagree in their forecasts and reasoning. Most academic experts view markets as efficient. By contrast, most households express a perspective we call “expected earnings reasoning”: they directly equate higher expected earnings with higher expected returns. Professionals are split between market efficiency, mispricing, and expected earnings reasoning. In detailed experiments, we dissect why households adopt expected earnings reasoning. We show that it arises from inattention to how stock-price changes affect investor costs—that is, how much investors must pay to acquire a claim to future cash flows—because the typical format and context of investment problems obscure these cost implications. Our results help connect a series of previously documented anomalies in expectation and trading data and highlight the importance of selective attention and context in shaping reasoning and belief formation.