Social interaction contributes to some traders' disposition effect. New data from an investment-specific social network linked to individual-level trading records builds evidence of this connection. To credibly estimate causal peer effects, I exploit the staggered entry of retail brokerages into partnerships with the social trading web platform and compare trader activity before and after exposure to these new social conditions. Access to the social network nearly doubles the magnitude of a trader's disposition effect. Traders connected in the network develop correlated levels of the disposition effect, a finding that can be replicated using workhorse data from a large discount brokerage.

Social interaction contributes to some traders’ disposition effect. New data from an investment-specific social network linked to individual-level trading records builds evidence of this connection. To credibly estimate causal peer effects, I exploit the staggered entry of retail brokerages into partnerships with the social trading web platform and compare trader activity before and after exposure to these new social conditions. Access to the social network nearly doubles the magnitude of a trader’s disposition effect. Traders connected in the network develop correlated levels of the disposition effect, a finding that can be replicated using workhorse data from a large discount brokerage.

We show that constraints can improve financial decision-making by disciplining behavioral biases. In financial markets, restrictions on leverage limit traders’ ability to borrow to open new positions. We demonstrate that regulation that restricts the provision of leverage to retail traders improves trading performance. By increasing the opportunity cost of postponing the realization of losses, leverage constraints improve traders’ market timing and reduce their disposition effect. We replicate these findings in two distinct experimental settings, further isolating the mechanism and demonstrating generality of the results. The interaction between constraints and behavioral biases has implications for policy and choice architecture.

This paper provides novel evidence on the real and financial market effects of legal institutions. Our analysis exploits persistent and externally imposed differences in court enforcement that arose when the U.S. Congress assigned state courts to adjudicate contracts on a subset of Native American reservations. Using area-specific data on small business lending, we find that reservations assigned to state courts, which enforce contracts more predictably than tribal courts, have stronger credit markets. Moreover, the law-driven component of credit market development is associated with significantly higher per capita income, with stronger effects in sectors that depend more on external financing.

We study the effect of personal wealth on entrepreneurial decisions using data on mineral payments from Texas shale drilling to individuals throughout the United States. Large cash windfalls increase business formation by 0.8 to 2.1 percentage points, but do not affect transitions to self-employment. By contrast, cash windfalls significantly extend self-employment spells, but do not affect the duration of business ownership. Our findings help reconcile contrasting findings in prior work: liquidity constraints have different effects on entrepreneurial activity that may depend on the entrepreneur’s motivations.