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.

Background Child maltreatment has serious short and long‐term negative impacts for those experiencing it. Child maltreatment occurring in institutional settings has recently received substantial attention. However, evidence about the effectiveness of interventions that prevent, disclose, respond to, or treat maltreatment that has occurred in these environments is fragmented and can be difficult to access. This evidence and gap map (EGM) collates this research evidence. It was developed as a resource for stakeholders operating in the child health, welfare and protection sectors, including practitioners, organisational leaders, policy developers and researchers, wanting to access high quality evidence on interventions addressing institutional child maltreatment. Objectives The objectives of this EGM were twofold: (a) To provide a structured and accessible collection of existing evidence from finalised and ongoing overviews of systematic reviews, systematic reviews and effectiveness studies of interventions addressing institutional child maltreatment—for those who work to fund, develop, implement and evaluate interventions aimed at ensuring children's safety in institutional settings; (b) to identify gaps in the available evidence on interventions addressing institutional child maltreatment—thereby helping to inform the research agendas of funders and other organisations. Search Methods A comprehensive search strategy identified relevant studies from published and grey literature, comprising: (1) 10 electronic academic databases; (2) five trial and systematic review registries; (3) nine organisational websites; (4) websites and reference lists of inquiry reports associated with seven international inquiries into child abuse and (4) the lists of included studies within systematic reviews identified by the search strategy. Members of this EGM's Subject Matter Experts group were also invited to forward relevant unpublished studies or grey literature. Selection Criteria The selection criteria were developed to identify finalised and ongoing overviews of reviews, systematic reviews and primary studies that reported on the effectiveness of interventions addressing child maltreatment (including sexual abuse, physical abuse, neglect and emotional abuse) within institutional settings. Eligible effectiveness study designs included: randomised controlled trials (RCTs), nonrandomised trials, controlled before‐and‐after studies and quasi‐experimental studies. Reviews were eligible if they reported a systematic literature search strategy. Data Collection and Analysis All screening, data extraction, coding and critical appraisals were undertaken by two or more reviewers working independently, with discrepancies resolved via consensus or by a third reviewer. The titles and abstracts of studies identified by the search strategy were screened, and each full text of potentially relevant studies was further assessed for inclusion. Key data were extracted from all included studies and reviews. This included information about: p...

Faulty eyewitness testimony can be a notorious source of mistakes in the legal system potentially leading to wrongful convictions and miscarriages of justice. The current study examined the knowledge of a sample of police officers (n = 270) and psychologists (n = 63) in Indonesia regarding factors known to influence the validity of eyewitness testimony given by adults and children. Previous studies have documented that police and psychologists in Western countries have less-than-optimal knowledge about the psychology of eyewitness testimony. Similarly, our non-Western sample also demonstrated a lack of knowledge that may be damaging in the legal context such as the belief that recall of minor details indicates accuracy of memory. For both adult and child eyewitnesses, the psychologists performed significantly better than the police but at the item level these differences were small in size. Intriguingly, we also found that psychologists were more likely than the police officers to endorse the item about repression of memories. The findings show the need for teaching on the psychology of eyewitness testimony for professional groups involved in the legal arena.

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.

The widespread comorbidity observed across psychiatric disorders may be the result of processes such as assortative mating, gene-environment correlation, or selection into population studies. Between-family analyses of comorbidity are subject to these sources of bias, whereas within-family analyses are not. Because of Mendelian inheritance, alleles are randomly assigned within families, conditional on parental alleles. We exploit this variation to compare the structure of comorbidity across broad psychiatric polygenic scores when calculated either between-family (child polygenic scores) or within-family (child polygenic scores regressed on parental polygenic scores) in over 25,000 genotyped parent-offspring trios from the Norwegian Mother Father and Child Cohort study (MoBa). We fitted a series of factor models to the between- and within-family data, which consisted of a single genetic p-factor and a varying number of uncorrelated subfactors. The best-fitting model was identical for between- and within- family analyses and included three subfactors capturing variants associated with neurodevelopment, psychosis, and constraint, in addition to the genetic p-factor. Partner genetic correlations, indicating assortative mating, were not present for the genetic p-factor, but were substantial for the psychosis (b= 0.081;95% CI [0.038,0.124]) and constraint (b= 0.257;95% CI [0.075,0.439]) subfactors. When average factor levels for MoBa mothers and fathers were compared to a population mean of zero we found evidence of sex-specific participation bias, which has implications for the generalisability of findings from cohort studies. Our results demonstrate the power of the within-family design for better understanding the mechanisms driving psychiatric comorbidity and their consequences on population health.