PhD defence D.C. (Daphne) Truijens

Summary:

Recent discoveries in psychology and behavioral economics show that small, seemingly irrelevant, changes in how options are presented have large effects on the choices that people make. In this context, people often seem to be irrational decisionmakers. These so-called “behavioral insights” from behavioral economics and psychology have inspired researchers and policymakers alike to develop interventions, which aim to help people make better decisions for society and for themselves. Smaller plates lead to better sticking to diets, default opt-out registration systems lead to more people signing up as organ donors, and signs telling us about the neighbors spending less minutes in the shower leads people to save water. These changes in the choice environment are relatively simple and cost efficient. Behavioral insights even catalyzed an “evidence-based policy movement” in which many governments have implemented behavioral insight units or teams. From within these units, policy makers draw on scientific expertise about behavior to tackle complex societal issues such as energy usage, health decisions, and organ donor shortages.

The aim of this thesis is to investigate the evidence for behavioral policies. Such evidence for behavior change is subject to interpretation and debate. This thesis provides insights into how both the empirical evidence for behavioral policies (e.g., the experiments) and normative aspects of their interpretation (e.g., rationality evaluations) are generated and what this implies for evidence-based policymaking and policymakers. The central question is: on which underlying normative and empirical assumptions is the interpretation of evidence for behavioral policies based?