How wise is the crowd: Can we infer people are accurate and competent merely because they agree with each other?

Are people who agree on something more likely to be right and competent? Evidence suggests that people tend to make this inference. However, standard wisdom of crowds approaches only provide limited normative grounds. Using simulations and analytical arguments, we argue that when individuals make independent and unbiased estimates, under a wide range of parameters, individuals whose answers converge with each other tend to have more accurate answers and to be more competent.

Quantifying the scientific revolution.

The Scientific Revolution represents a turning point in the history of humanity. Yet it remains ill-understood, partly because of a lack of quantification. Here, we leverage large datasets of individual biographies ( = 22,943) and present the first estimates of scientific production during the late medieval and early modern period (1300-1850).

Desperation and inequality increase stealing: evidence from experimental microsocieties.

People facing material deprivation are more likely to turn to acquisitive crime. It is not clear why it makes sense for them to do so, given that apprehension and punishment may make their situation even worse. Recent theory suggests that people should be more willing to steal if they are on the wrong side of a 'desperation threshold'; that is, a level of resources critical to wellbeing.

Why is violence high and persistent in deprived communities? A formal model.

There is massive variation in rates of violence across time and space. These rates are positively associated with economic deprivation and inequality. They also tend to display a degree of local persistence, or 'enduring neighbourhood effects'.

Cultural diversity and wisdom of crowds are mutually beneficial and evolutionarily stable.

The ability to learn from others (social learning) is often deemed a cause of human species success. But if social learning is indeed more efficient (whether less costly or more accurate) than individual learning, it raises the question of why would anyone engage in individual information seeking, which is a necessary condition for social learning's efficacy. We propose an evolutionary model solving this paradox, provided agents (i) aim not only at information quality but also vie for audience and prestige, and (ii) do not only value accuracy but also reward originality-allowing them to alleviate herding effects.

Why do inequality and deprivation produce high crime and low trust?

Humans sometimes cooperate to mutual advantage, and sometimes exploit one another. In industrialised societies, the prevalence of exploitation, in the form of crime, is related to the distribution of economic resources: more unequal societies tend to have higher crime, as well as lower social trust. We created a model of cooperation and exploitation to explore why this should be.