• August 2021
• Article

Long-term nominal interest rates are surprisingly sensitive to high-frequency (daily or monthly) movements in short-term rates. Since 2000, this high-frequency sensitivity has grown even stronger in U.S. data. By contrast, the association between low-frequency changes (at 6- or 12-month horizons) in long- and short-term rates, which was also strong before 2000, has weakened substantially. This puzzling post-2000 pattern arises because increases in short rates temporarily raise the term premium component of long-term yields, leading long rates to temporarily overreact to changes in short rates. The frequency-dependent excess sensitivity of long-term rates that we observe in recent years is best understood using a model in which (i) declines in short rates trigger "rate-amplifying" shifts in investor demand for long-term bonds and (ii) the arbitrage response to these demand shifts is both limited and slow. We study, both theoretically and empirically, how such rate-amplifying demand can be traced to mortgage refinancing activity, investors who extrapolate recent changes in short rates, and investors who "reach for yield" when short rates fall. We discuss the implications of our findings for the validity of event-study methodologies and the transmission of monetary policy.

• August 2021
• Article

We provide evidence that bond fund managers misclassify their holdings, and that these misclassifications have a real and significant impact on investor capital flows. In particular, many funds report more investment grade assets than are actually held in their portfolios to important information intermediaries, making these funds appear significantly less risky. This results in pervasive misclassification across the universe of US fixed income mutual funds. The problem is widespread—resulting in up to 31.4% of funds being misclassified with safer profiles, when compared against their true, publicly reported holdings. “Misclassified funds”—i.e., those that hold risky bonds, but claim to hold safer bonds—appear to on-average outperform the low-risk funds in their peer groups. Within category groups, “Misclassified funds” moreover receive higher Morningstar Ratings (significantly more Morningstar Stars) and higher investor flows. However, when we correctly classify them based on their actual risk, these funds are mediocre performers. These Misclassified funds also significantly underperform precisely when junk-bonds crash in returns. Misreporting is stronger following several quarters of large negative returns.

• July 2021
• Case

This case explores the decision that Bill Ackman, CEO and founder of the hedge fund Pershing Square Capital, was considering in late February 2020 about hedging the exposure of the fund’s portfolio from the potential financial fallout ensuing from an extreme event like a global pandemic. Bill Ackman had become increasingly concerned about the hedge fund’s exposure to a novel, highly infections, and lethal coronavirus that was spreading across the globe. Ackman and his team needed to decide whether this was a risk worth hedging, and if so, which hedging instruments would best balance risk mitigation, explicit costs (fees and premia), opportunity costs, and the long-run objectives of the fund. Ackman and his team considered fully liquidating their portfolio, as well as hedging it with futures, options, and credit default swaps. For each alternative, they also needed to determine the optimal size and maturity of the hedging position, after accounting for uncertainty over the trajectory of the virus. This case provides students with ample opportunities to analyze and understand tail risk and how to manage it in practice, including explicit calculations of position sizing, costs, risks, and benefits of hedging alternatives.