A Bound on Price Impact and Disagreement

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Event details

Date 16.12.2025
Hour 12:1513:15
Speaker Philippe van der Beck - Harvard Business School
Location
UNIL, Extranef, room 126
Category Conferences - Seminars
Event Language English

High asset price volatility alongside low portfolio flows reveals a fundamental trade-off between investor disagreement and price impact: When volatility is high but flows are small, investors must either largely agree with each other or be insensitive to price changes, implying large price impacts of small flows. We formalize this relationship in a price impact bound based on price volatility, flow volatility, and investor agreement. Applying our bound to U.S. equities yields large price impacts, implying that flows are central to understanding price dynamics. Our bounds align with event-study estimates while revealing novel patterns across horizons, assets, and aggregation levels.