Default Effect

Real-world examples

Organ donation rates in countries with 'opt-out' default policies exceed 90%, compared to under 20% in countries with 'opt-in' policies.

• Retirement plans with automatic enrollment see far higher participation than opt-in plans with identical terms.
• Software that ships with privacy settings pre-selected shapes what most users end up sharing.

How to design for it (nudge strategy)

The evidence (4)

• Overcoming Saving Inertia with Future Commitments

  Finance · Average Retirement Saving Rate: 3.5% → 13.6% (+10.1 pts) · n = 3 companies, 1,200 employees

• Organ Donation Registration Rates and Presumed Consent

  Healthcare · Donor Consent Registration Rate: 18% → 99.1% (+81.1 pts) · n = Cross-national European Comparison

• Reducing Cart Abandonment by Mitigating Choice Overload

  E-commerce · Completed Purchase Checkout Rate: 71.2% → 84.8% (+13.6 pts) · n = 45,000 sessions

• Mitigating Algorithm Aversion Through Output Control

  Finance · Adoption Rate of the Algorithmic Forecast: 15% → 88% (+73.0 pts) · n = 3 experimental studies, 1,200 trials

Key research

• Nudge: Improving Decisions About Health, Wealth, and HappinessRichard H. Thaler, Cass R. Sunstein · Yale University Press (2008)
• Active vs. Passive Decisions and Crowd-Out in Retirement Savings AccountsRaj Chetty, John N. Friedman, Søren Leth-Petersen, Torben Heien Nielsen, Tore Olsen · The Quarterly Journal of Economics / NBER (2014)
• Applying Insights from Behavioral Economics to Policy DesignBrigitte C. Madrian · Annual Review of Economics / NBER (2014)

Related biases