This project develops a model of how individual form beliefs and make choices that is grounded in human psychology. Economics views humans as fully rational agents, who use the information at their disposal to form the most accurate beliefs possible and to make the best possible choices. In the last thirty years or so, psychologists and behavioral economists have collected vast experimental and field evidence showing that human beliefs and behavior depart in certain systematic ways from the predicates of full rationality, and that these departures have profound influence on the working of real world markets (e.g. financial markets).
Notwithstanding this evidence, the rational approach is still dominant. This is due to the lack of a generally applicable model of human psychology. On the one hand, different departures from rationality are often explained invoking different psychological principles. The proliferation of factors and “explanations” makes it hard for researchers to obtain general and widely applicable lessons. On the other hand, existing attempts to model psychological influences are tailored to specific markets or decisions, which makes it hard to transport these models into different contexts. Against this complex and intricate web of results, the great advantage of the rational approach is to offer a general, coherent, and widely applicable model of human behavior.
In this project we purport to develop a psychologically founded alternative to rational behavior by following a two pronged strategy. The first is unification. We seek to explain a large number of departures from rational behavior by relying on a simple yet powerful general principle: the idea that our belief or decisions are excessively influenced by information that is unusual or different, while we tend to neglect relevant but non salient information. This principle is grounded on a vast literature in the cognitive sciences stressing the importance of limited selective attention. The first goal of the project, then, is to show that limited and selective human attention offers a parsimonious way to rationalize many disparate anomalies in human behavior. The second pillar of the project, then, is to build a general economic model embodying selective and limited attention and to apply the model to analyze different domains of real world behavior and markets. In particular, we used our approach to analyze the formation of beliefs in financial markets, the determinants of beliefs and stereotypes in social domains involving for instance racial, gender, or political groups, as well as human choice among different consumer goods.
Developing an psychologically founded yet generally applicable alternative to rational behavior is very important for two reasons. In the first place, because it deepens our understanding of social phenomena, be they market or non-market ones. In the second place, because having a more realistic and accepted model of human behavior has critical implications for public policy. If individual decisions are rational and optimal under given conditions, then there is limited room for policy to improve upon social and market outcomes, and relevant policy tools effectively amount to material incentives. If instead phenomena like financial crises, discrimination, political polarization are due to erroneous beliefs and decisions by the market participants or relevant players, the role and tools of social policy have to be rethought. In particularly, policy is likely to play a more important role in this world, and material incentives may be less relevant. Corrective action on beliefs may achieve larger results, as several recent studies are indeed starting to indicate.
