An initially false study linking a food to longevity causes health-conscious people to adopt it. Subsequent studies show a stronger link, not due to the food, but because the people eating it are healthier in general, magnifying the initial error.
Economic models assume information is always valuable. However, few at-risk individuals get tested for Huntington's disease, preferring the hope of a good outcome over the certainty of a devastating diagnosis, even if knowing could optimize life decisions.
When facing a tough choice, people often frame it as "do X or not." A better framework is to define the specific, concrete alternative (e.g., "send kid to daycare or hire a nanny" vs. "or quit my job"). This clarifies the true trade-offs involved.
When facing a crisis like COVID, waiting for perfect data before acting is not a 'safe' option. The status quo of inaction often carries its own significant, accumulating costs—like student learning loss—that must be factored into the decision.
The public narrative around breastfeeding suggests it's crucial for long-term outcomes like IQ. However, data analysis shows the actual benefits are modest and mostly short-term (e.g., digestive health), a stark mismatch with the societal pressure placed on mothers.
After publishing a famous paper, economist Emily Oster spent years gathering better data that invalidated her own findings. She then published a new paper retracting her original conclusion—a rare and commendable act of intellectual honesty that should be celebrated.
Frustrated by the lack of official data on COVID in schools, economist Emily Oster created her own data collection system with a simple Google Form. It grew into a national dashboard, showing that motivated individuals can create essential data when institutions are too slow.