[We propose a theory of momentum and reversal based on flows between investment funds. Flows are triggered by changes in fund managers' efficiency, which investors either observe directly or infer from past performance. Momentum arises if flows exhibit inertia, and because rational prices underreact to expected future flows. Reversal arises because flows push prices away from fundamental values. Besides momentum and reversal, flows generate comovement, lead-lag effects, and amplification, with these being larger for high idiosyncratic risk assets. A calibration of our model using evidence on mutual fund returns and flows generates sizeable Sharpe ratios for momentum and value strategies.]

[We propose a clientele-based model of the yield curve and optimal maturity structure of government debt. Clienteles are generations of agents at different lifecycle stages in an overlapping-generations economy. An optimal maturity structure exists in the absence of distortionary taxes and induces efficient intergenerational risksharing. If agents are more risk-averse than log, then an increase in the long-horizon clientele raises the price and optimal supply of long-term bonds—effects that we also confirm empirically in a panel of OECD countries. Moreover, under the optimal maturity structure, catering to clienteles is limited and long-term bonds earn negative expected excess returns.]

We propose a theory of momentum and reversal based on flows between investment funds. Flows are triggered by changes in fund managers' efficiency, which investors either observe directly or infer from past performance. Momentum arises if flows exhibit inertia, and because rational prices underreact to expected future flows. Reversal arises because flows push prices away from fundamental values. Besides momentum and reversal, flows generate comovement, lead-lag effects, and amplification, with these being larger for high idiosyncratic risk assets. A calibration of our model using evidence on mutual fund returns and flows generates sizeable Sharpe ratios for momentum and value strategies.

We propose a clientele-based model of the yield curve and optimal maturity structure of government debt. Clienteles are generations of agents at different lifecycle stages in an overlapping-generations economy. An optimal maturity structure exists in the absence of distortionary taxes and induces efficient intergenerational risksharing. If agents are more risk-averse than log, then an increase in the long-horizon clientele raises the price and optimal supply of long-term bonds—effects that we also confirm empirically in a panel of OECD countries. Moreover, under the optimal maturity structure, catering to clienteles is limited and long-term bonds earn negative expected excess returns.