Kahneman and Tversky's 1979 article on Prospect Theory is one of the most influential papers across all of the behavioural sciences. The study tested a series of binary financial (risky) choices, ultimately concluding that judgments formed under uncertainty deviate significantly from those presumed by expected utility theory, which was the prevailing theoretical construct at the time. In the forty years since publication, this study has had a remarkable impact on science, policy, and other real-world applications. At the same time, a number of critiques have been raised about its conclusions and subsequent constructs that were founded on it, such as loss aversion. In an era where such presumed canonical theories have increasingly drawn scrutiny for inability to replicate, we attempted a multinational study of N = 4,099 participants from 19 countries and 13 languages. The same methods and procedures were used as in the original paper, adjusting only currencies to make them relative to current values, and requiring all participants to respond to all items. Overall, we found that results replicated for 94% of the 17 choice items tested. At most, results from the 1979 study were attenuated in our findings, which is most likely due to a more robust sample. Twelve of the 13 theoretical contrasts presented by Kahneman and Tversky also replicated, with a further 89% replication rate of the total contrasts possible when separating by location, up to 100% replication in some countries. We conclude that the principles of Prospect Theory replicate beyond any reasonable thresholds, and provide a number of important insights about replications, attenuation, and implications for the study of human decision-making at population-level.

Beliefs about polarization have significant social consequences, whether accurate or not [1][2][3][4] . They also complicate the study of social issues as reported attitudes might be impacted by inaccurate out-group perceptions and thus make conflicts around a specific issue or policy appear more severe than they actually are 5 . This can result in significant distortions in numerous behaviours, including health, voting and financial choices, each of which has consequences on population wellbeing 6 .There is growing interest in the origins of polarization across populations as well as its features and impacts across communities and society 7,8 . This interest is global and includes both scientific research as well as general public interest 9,10 . As polarization seemingly permeates a growing number of personal and public domains, there is some sense of renewed urgency to understand it and its effects more deeply 11,12 . This includes extending study to understand the extent of polarization on community and global levels.However, with increasing interest in polarization itself, broadening evidence indicates that inaccuracies in perceptions of how the out-group feels about the in-group can be harmful 13 . The origin of these 'meta-perceptions' may be rooted in negative stereotypes that individuals feel have been applied to them, often incorrectly 14 . This results in an inaccurate perception of differences in beliefs and attitudes between groups 15 , which can have negative results for individuals 16,17 . On a population level, such misperceptions can even result in overstated reactions that exacerbate existing biases 18 .To investigate roots and moderators of polarization across groups, Lees and Cikara 13 ran a series of experiments with US participants identifying as Republican or Democrat. In what they refer

Economic inequality is associated with preferences for smaller, immediate gains over larger, delayed ones. Such temporal discounting may feed into rising global inequality, yet it is unclear whether it is a function of choice preferences or norms, or rather the absence of sufficient resources for immediate needs. It is also not clear whether these reflect true differences in choice patterns between income groups. We tested temporal discounting and five intertemporal choice anomalies using local currencies and value standards in 61 countries (N = 13,629). Across a diverse sample, we found consistent, robust rates of choice anomalies. Lower-income groups were not significantly different, but economic inequality and broader financial circumstances were clearly correlated with population choice patterns.

A pervading global narrative suggests that political polarisation is increasing in the US and around the world. Beliefs in increased polarisation impact individual and group behaviours regardless of whether they are accurate or not. One driver of polarisation are beliefs about how members of the out-group perceive us, known as group meta-perceptions. A 2020 study by Lees and Cikara in US samples suggests that not only are out-group meta-perceptions highly inaccurate, but informing people of this inaccuracy reduces negative beliefs about the out-group. Given the importance of these findings for understanding and mitigating polarisation, it is essential to test to what extent they generalise to other countries. We assess that generalisability by replicating two of the original experiments in 10,207 participants from 26 countries in the first experiment and 10 in the second. We do this by studying local group divisions, which we refer to as fault lines. In line with our hypotheses, results show that the pattern found in the US broadly generalises, with greater heterogeneity explained by specific policies rather than between-country differences. The replication of a simple disclosure intervention in the second experiment yielded a modest reduction in negative motive attributions to the out-group, similar to the original study. These findings indicate first that inaccurate and negative group meta-perceptions are exhibited in a large number of countries, not only the US, and that informing individuals of their misperceptions can yield positive benefits for intergroup relations. The generalisability of these findings highlights a robust phenomenon with major implications for political discourse worldwide.

Kahneman and Tversky’s 1979 article on Prospect Theory is one of the most influential papers across all of the behavioural sciences. The study tested a series of binary financial (risky) choices, ultimately concluding that judgments formed under uncertainty deviate significantly from those presumed by expected utility theory, which was the prevailing theoretical construct at the time. In the forty years since publication, this study has had a remarkable impact on science, policy, and other real-world applications. At the same time, a number of critiques have been raised about its conclusions and subsequent constructs that were founded on it, such as loss aversion. In an era where such presumed canonical theories have increasingly drawn scrutiny for inability to replicate, we attempted a multinational study of N = 4,099 participants from 19 countries and 13 languages. The same methods and procedures were used as in the original paper, adjusting only currencies to make them relative to current values, and requiring all participants to respond to all items. Overall, we found that results replicated for 94% of the 17 choice items tested. At most, results from the 1979 study were attenuated in our findings, which is most likely due to a more robust sample. Twelve of the 13 theoretical contrasts presented by Kahneman and Tversky also replicated, with a further 89% replication rate of the total contrasts possible when separating by location, up to 100% replication in some countries. We conclude that the principles of Prospect Theory replicate beyond any reasonable thresholds, and provide a number of important insights about replications, attenuation, and implications for the study of human decision-making at population-level.