Behavioural feedback: Do individual choices influence scientific results?
29 May 2019, 1:00 pm–2:00 pm
In this seminar, Emily Oster examines feedback patterns between scientific findings and health behaviours. She investigates whether there are selective behavioural responses to new research findings on health behaviours, and to what degree these may bias later observational studies on these same behaviours.
This event is free.
Room G0326 Bedford WayLondonWC1H 0AP
Consider a case in which a new research finding links a health behaviour with good health outcomes. A possible consequence is additional take-up of this behaviour among individuals who engage in other positive health behaviours. If this occurs, then later analysis of observational data may be biased by the change in selection. Even sampling-driven false positive results may be confirmed in subsequent work.
In this seminar, Emily Oster asks whether these dynamic biases occur, whether they are quantitatively important in empirical settings, and whether standard selection-on-observables adjustments are sufficient to address them.
Using data from vitamin supplementation and diet behaviours, she shows that selection responds endogenously to health recommendations. When behaviours are more recommended, they are more frequently adopted by individuals who engage in other positive health behaviours (e.g., not smoking, exercising) and who are better educated and richer. Furthermore, when behaviours are more recommended, they are more strongly associated with positive health outcomes, including survival, weight and heart health.
Oster’s analysis indicates that behavioural feedback effects are large and that adjustment for selection on observables is insufficient to address the bias. This suggests research findings themselves may endogenously bias observational studies.
About the Speaker
Professor Emily Oster
Emily Oster is a Professor of Economics at Brown University. Her work focuses on health, development, and methodological issues. In addition, she is the author of popular science books on pregnancy and parenting.More about Professor Emily Oster