An in-depth analysis of replies to COVID-19 vaccination outreach reveals thanks, angst — and much more.

Ride-hailing apps have allowed more binging—and increased demand for bartenders

When people make decisions with a pre-selected choice option – a ‘default’ – they are more likely to select that option. Because defaults are easy to implement, they constitute one of the most widely employed tools in the choice architecture toolbox. However, to decide when defaults should be used instead of other choice architecture tools, policy-makers must know how effective defaults are and when and why their effectiveness varies. To answer these questions, we conduct a literature search and meta-analysis of the 58 default studies (pooled n = 73,675) that fit our criteria. While our analysis reveals a considerable influence of defaults (d = 0.68, 95% confidence interval = 0.53–0.83), we also discover substantial variation: the majority of default studies find positive effects, but several do not find a significant effect, and two even demonstrate negative effects. To explain this variability, we draw on existing theoretical frameworks to examine the drivers of disparity in effectiveness. Our analysis reveals two factors that partially account for the variability in defaults’ effectiveness. First, we find that defaults in consumer domains are more effective and in environmental domains are less effective. Second, we find that defaults are more effective when they operate through endorsement (defaults that are seen as conveying what the choice architect thinks the decision-maker should do) or endowment (defaults that are seen as reflecting the status quo). We end with a discussion of possible directions for a future research program on defaults, including potential additional moderators, and implications for policy-makers interested in the implementation and evaluation of defaults.

In a meta-analysis of real-life experiments drawn from food science, nutrition, health economics, marketing and psychology, the authors find that behavioural nudges - facilitating action rather than providing knowledge or inducing feelings - can reduce daily energy intake by up to 209 kcal, the same number of calories as in 21 cubes of sugar.

Our work published this week analyses all 111 cases studies of behavioral techniques used by governments compiled by the OECD (Organisation for Economic Co-operation and Development). Our analysis demonstrates that none of the techniques used have scientific proven effectiveness.