An investor receives utility bursts from realizing gains and losses at the individual stock level and dynamically allocates his mental budget between risky and risk‐free assets at the trading account level. Using savings, he reduces his stockholdings and is more willing to realize losses. Using leverage, he increases his stockholdings beyond his mental budget and is more reluctant to realize losses. While leverage strengthens the disposition effect, introducing leverage constraints mitigates it. Our model predicts that investors with stocks in deep losses sell them either immediately or after stocks rebound a little.

We study aversion to model ambiguity and misspecification in dynamic portfolio choice. Risk‐averse investors (relative risk aversion ) fear return persistence, while risk‐tolerant investors () fear mean reversion, when confronting model misspecification concerns of identically and independently distributed (IID) returns. The intuition is that risk‐averse investors, who want to hedge intertemporally, endogenously fear return persistence, which precludes hedging. A log investor is myopic and unaffected by model misspecification, therefore only worrying about model ambiguity. Our model can generate belief scarring, nonparticipation in equity markets, and extrapolative return expectations. Extending beyond IID returns, we study model misspecification for a mean‐reverting Sharpe ratio.

We study the asset allocation and investment performance of U.S. private foundations that support the charitable sector. Large foundations generated positive risk‐adjusted returns before 2008, driven by early access to private equity and venture capital funds, but have underperformed since. The median foundation underperforms by more than 100 bps. Foundations with concentrated stock holdings achieve higher returns but assume more risk. Due to the constraints imposed by the 5% minimum spending rule and accommodating monetary policy, foundations increase risk‐taking and reach for yield. Over time, a conservative asset allocation decreases real wealth, reducing charitable giving.

We propose a theory of coordination and influence among blockholders. Privately informed activists time their trades in sequence to lower acquisition costs, prompting a strategic use of order flows: leader activists create trading gains for their followers, ultimately influencing their willingness to bear greater value‐enhancing intervention costs. Through this channel, informed trades can exhibit predictability, in sharp contrast with Kyle (1985, Econometrica 53, 1315–1335). We explain how this novel predictability shapes free‐rider problems affecting governance, and how it produces price abnormalities analogous to those documented empirically. We also uncover how private information interdependence can be a key catalyst for the mechanism studied.

I propose a dynamic equilibrium model of rental markets that endogenously gives rise to defaults on rents and evictions. In the model, eviction protections make it harder to evict delinquent renters, but higher default costs to landlords increase equilibrium rents. I quantify the model using micro data on evictions, rents, and homelessness. I find that stronger eviction protections exacerbate housing insecurity and lower welfare. The key empirical driver of this result is the persistent nature of risk underlying rent delinquencies. Rental assistance reduces housing insecurity and improves welfare because it lowers the likelihood that renters default ex ante.