I find that approximately 30% of price fluctuations in the Fama-French size and value factors are nonfundamental price pressures driven by correlated fund flows, which generate price movements that revert over time. Is this really demand-based price pressure? I show that the price effects happen exclusively in periods when mutual funds place trades, a fact that is difficult to explain using traditional mechanisms such as unobserved investor preference changes. The estimated price elasticity is also consistent with other studies. Overall, my findings show that a sizable fraction of size and value factor movements do not represent economic risk.

Corporate bond prices are slow to respond to default risk and interest rate shocks, as proxied by firm-level stock returns and Treasury returns, respectively. Furthermore, the underreaction is risk-specific: bonds with better credit quality underreact more to default risk, while those with worse quality underreact more to interest rates. The underreactions imply substantial out-of-sample return predictability, and investors appear to be leaving too much money on the table. The results are consistent with behavioral inattention models in which investors endogenously allocate more attention to payoff-relevant (or salient) risks, and they are not explained by traditional trading friction mechanisms.

Using comprehensive data on U.S. corporate bond trades since 2002, we find evidence that retail bond investors overrely on untimely credit ratings to their financial detriment. Specifically, they appear to select bonds by first screening on a credit rating and then sorting by yield, buying the highest-yielding bonds within each rating level. Because yields lead credit rating changes, selecting on yield-within-rating means that retail investors systematically trade in the opposite direction of changing fundamentals, buy in advance of credit downgrades and defaults, and materially underperform a diversified portfolio. Our study provides new evidence of ill-informed retail trading in a market that is thought to be relatively sophisticated, corroborates regulators’ concerns about investor overreliance on credit ratings, and contributes to the academic literature on the roles and consequences of credit ratings in debt markets.

Classical asset pricing models predict that optimizing investors exhibit extremely high demand elasticities, while empirical estimates are significantly lower—by three orders of magnitude. To reconcile this disparity, we introduce a novel decomposition of investor demand elasticity into two key components: “price pass-through”, which captures how price movements forecast returns, and “unspanned returns”, reflecting a stock’s lack of perfect substitutes. In a factor model framework, we show that unspanned returns become significant when models include “weak factors”. Classical models overestimate demand elasticity by assuming both very low unspanned returns and high price pass-throughs, assumptions that are inconsistent with empirical evidence.

We show that mutual fund investors rely on simple signals and likely do not engage in sophisticated learning about managers’ alpha as widely believed. Simplistic performance chasing best explains aggregate flows to the mutual fund space and flows across funds. These results hold for both actively managed and passive index funds. Empirical patterns commonly interpreted as reflecting learning about managerial skill also appear in falsification tests and are mechanical. Our results are consistent with the view that, on average, households are homo sapiens with limited financial sophistication rather than hyperrational alpha-maximizing agents, as often assumed in the literature.

We show that mutual fund ratings generate correlated demand that creates systematic price fluctuations. Mutual fund investors chase fund performance via Morningstar ratings. Until June 2002, funds pursuing the same investment style had highly correlated ratings. Therefore, rating-chasing investors directed capital into winning styles, generating style-level price pressures, which reverted over time. In June 2002, Morningstar reformed its methodology of equalizing ratings across styles. Style-level correlated demand via mutual funds immediately became muted, significantly altering the time-series and cross-sectional variation in style returns.

We show that demand effects generated by institutional frictions can influence systematic return predictability patterns in stocks and mutual funds. Identification relies on a reform to the Morningstar rating system, which we show caused a structural break in style-level positive feedback trading by mutual funds. As a result, momentum-related factors in stocks, as well as performance persistence and the “dumb money effect” in mutual funds, experienced a sharp decline. Consistent with the proposed channel, return predictability declined right after the reform, was limited to the U.S. market, and was concentrated in factors and mutual funds most exposed to the mechanism.

We show that attention constraints on decision-makers create barriers to financial inclusion. Using administrative data on retail loan-screening processes, we find that attention-constrained loan officers exert less effort reviewing applicants of lower socioeconomic status (SES) and reject them more frequently. More importantly, when externally imposed increases in loan officers’ workloads tighten attention constraints, loan officers are even more prone to quickly reject low-SES applicants but quickly accept very high-SES applicants without careful review. Such selective attention allocation further widens the approval rate gap between high- and low-SES applicants—a unique prediction of this attention-based mechanism.