Four basic personalities, but Envious the most common

Organisation: Position: Deadline Date: Location:

A study on human behaviour has revealed that 90% of the population can be classified into four basic personality types: Optimistic, Pessimistic, Trusting and Envious. However, the latter of the four types, Envious, is the most common, with 30% compared to 20% for each of the other groups.

This is one of the main conclusions of a study by researchers from Universidad Carlos III de Madrid, together with colleagues from the universities of Barcelona, Rovira i Virgili and Zaragoza. The study analysed the responses of 541 volunteers to hundreds of social dilemmas, with options leading to collaboration or conflict with others, based on individual or collective interests.

Specifically, this work is part of game theory, a branch of mathematics with applications in sociology and economics, which examines the behaviour of people when they face a dilemma and have to make decisions. These decisions will have different consequences which will also depend on what the other party involved decides to do. “Those involved are asked to participate in pairs, these pairs change, not only in each round, but also each time the game changes. So, the best option could be to cooperate or, on the other hand, to oppose or betray…

In this way, we can obtain information about what people do in very different social situations,” explained one of the authors of the study, Anxo Sánchez, who is a professor in GISC (Grupo Interdisciplinar de Sistemas Complejos / Interdisciplinary Group of Complex Systems), which is part of the department of mathematics at Universidad Carlos III de Madrid (UC3M).

According to Yamir Moreno, who is the co-ordinator of the Cosnet group (Grupo de Redes y Sistemas Complejos / Networks and Complex Systems Group) at BIFI (Instituto de Biocomputación y Física de Sistemas Complejos / Institute of Biocomputation and the Physics of Complex Systems) at the Universidad de Zaragoza, and also president of the Sociedad de Sistemas Complejos (Complex Systems Society), “The results go against certain theories; the one which states that humans act purely rationally for example, and, therefore, they should be taken into consideration in redesigning social and economic policies, as well as those involved in cooperation.” He goes on to say that, “these types of studies are important because they improve existing theories on human behaviour by giving them an experimental base.”

After carrying out this kind of social experiment, the researchers developed a computer algorithm which set out to classify people according to their behaviour. The computer algorith organised 90% of people into four groups: the largest group, accounting for 30%, being the Envious – those who don’t actually mind what they achieve, as long as they’re better than everyone else; next are the Optimists – who believe that they and their partner will make the best choice for both of them – on 20%. Also on 20% are the Pessimists – who select the option which they see as the lesser of two evils – and the Trusting group – who are born collaborators and who will always cooperate and who don’t really mind if they win or lose.

There is a fifth, undefined group, representing 10%, which the algorithm is unable to classify in relation to a clear type of behaviour. The researchers argue that this allows them to infer the existence of a wide range of subgroups made up of individuals who do not respond in a determined way to any of the outlined models.

Socially relevant situations that involve strategic interactions are widespread among animals and humans alike. To study these situations, theoretical and experimental research has adopted a game theoretical perspective, generating valuable insights about human behavior. However, most of the results reported so far have been obtained from a population perspective and considered one specific conflicting situation at a time. This makes it difficult to extract conclusions about the consistency of individuals’ behavior when facing different situations and to define a comprehensive classification of the strategies underlying the observed behaviors. We present the results of a lab-in-the-field experiment in which subjects face four different dyadic games, with the aim of establishing general behavioral rules dictating individuals’ actions. By analyzing our data with an unsupervised clustering algorithm, we find that all the subjects conform, with a large degree of consistency, to a limited number of behavioral phenotypes (envious, optimist, pessimist, and trustful), with only a small fraction of undefined subjects. We also discuss the possible connections to existing interpretations based on a priori theoretical approaches. Our findings provide a relevant contribution to the experimental and theoretical efforts toward the identification of basic behavioral phenotypes in a wider set of contexts without aprioristic assumptions regarding the rules or strategies behind actions. From this perspective, our work contributes to a fact-based approach to the study of human behavior in strategic situations, which could be applied to simulating societies, policy-making scenario building, and even a variety of business applications.

Julia Poncela-Casasnovas, Mario Gutiérrez-Roig, Carlos Gracia-Lázaro, Julian Vicens, Jesús Gómez-Gardeñes, Josep Perelló, Yamir Moreno, Jordi Duch, Angel Sánchez


The study worked by asking people about a range of different situations, each of which involved hunting, says a Cape Times report. So, for example, people might be told that two people can hunt for deer by working together, or they can go it alone and catch rabbits. The respondents were then told to decide which of the things they’d do.

Someone who is envious would look for rabbits because they’d be able to do more for themselves, for instance. Optimists would work together because that’s the best option for all. The pessimist would opt for rabbits because there’s more chance of at least catching something. And a trusting person would opt for co-operation, working together to catch the deer.

And, the report says, 30% of the people in the study were envious. The largest group was mostly looking to triumph and beat the other hunter – irrespective of whether that actually led to better results all round.

Only a small fraction of people didn’t fit into any of the groups at all, despite the varied range of questions, according to the researchers from Universidad Carlos III de Madrid.

The researchers said the study was inspired by the fact that many people find using games to be a useful way of finding out about human behaviour. But most of those studies just look at one situation and often one specific part of the population to work out how people act.

As such, it is hard to generalise about behaviour and understand how consistent it is across different situations.

Science Daily report
Science Advances abstract
Full Cape Times report

Receive Medical Brief's free weekly e-newsletter

Related Posts

Thank you for subscribing to MedicalBrief

MedicalBrief is Africa’s premier medical news and research weekly newsletter. MedicalBrief is published every Thursday and delivered free of charge by email to over 33 000 health professionals.

Please consider completing the form below. The information you supply is optional and will only be used to compile a demographic profile of our subscribers. Your personal details will never be shared with a third party.

Thank you for taking the time to complete the form.