Big Five personality traits

In psychology, the Big Five personality traits denotes a certain approach to the theory of personality.

Overview
The big five personality traits can be summarized as follows:

Neuroticism - A tendency to easily experience unpleasant emotions such as anxiety, anger, or depression.

Extroversion - Energy, surgency, and the tendency to seek stimulation and the company of others.

Agreeableness - A tendency to be compassionate and cooperative rather than suspicious and antagonistic towards others.

Conscientiousness - A tendency to show self-discipline, act dutifully, and aim for achievement.

Openness to experience - Appreciation for art, emotion, adventure, and unusual ideas; imaginative and curious.

These traits are usually measured as percentile scores, with the average mark at 50%; so for example, a Conscientiousness rating in the 80th percentile indicates a greater than average sense of responsibility and orderliness, while an Extroversion rating in the 5th percentile indicates an exceptional need for solitude and quiet.

Origins
In 1936 Gordon Allport and H. S. Odbert hypothesized that:

Those individual differences that are most salient and socially relevant in people’s lives will eventually become encoded into their language; the more important such a difference, the more likely is it to become expressed as a single word.

This statement has become known as the Lexical Hypothesis.

Allport and Odbert had worked through two of the most comprehensive dictionaries of the English language available at the time, and extracted 18,000 personality-describing words. From this gigantic list they extracted 4500 personality-describing adjectives which they considered to describe observable and relatively permanent traits.

In 1946 Raymond Cattell used the emerging technology of computers to analyse the Allport-Odbert list. He organized the list into 181 clusters and asked subjects to rate people whom they knew by the adjectives on the list. Using factor analysis Cattell generated twelve factors, and then included four factors which he thought ought to appear. The result was the hypothesis that individuals describe themselves and each other according to sixteen different, independent factors.

With these sixteen factors as a basis, Cattell went on to construct the 16PF Personality Questionnaire, which remains in use by universities and businesses for research, personnel selection and the like. Although subsequent research has failed to replicate his results, and it has been shown that he retained too many factors, the current 16PF takes these findings into account and is considered to be a very good test. In 1963, W.T. Norman replicated Cattell’s work and suggested that five factors would be sufficient.

Hiatus in research
For the next seventeen years, the changing Zeitgeist made the publication of personality research difficult. Social psychologists argued that behavior is not stable, but varies with context, so that predicting behavior by personality test was impossible. They further argued that character, or personality, is something humans impose on people in order to maintain an illusion of consistency in the world. Furthermore, Walter Mischel in his 1968 book Psychological Assessment asserted that personality tests could not predict behavior with a correlation of more than 0.3.

Around 1980, three developments brought personality research into the modern era: personal computers, statistical aggregation, and the Big Five.

Personal computers
Before the advent of personal computers, psychologists wishing to conduct large scale statistical analysis needed to rent access to a mainframe. However, once personal computers become widely available, they could do this work on their desktops. Therefore anybody could easily re-examine the Allport-Odbert list. The question remained as to why they would do so, given that it had seemingly already been established that personality was an illusion.

Statistical aggregation
It was argued that personality psychologists had considered behavior from the wrong perspective. Instead of trying to predict single instances of behavior, which was unreliable, it was thought that researchers should try to predict patterns of behavior. As a result correlations soared from .3 to .8 and it seemed that “personality” did in fact exist. Social psychologists still argue that we impose consistency on the world, but with statistical aggregation it could be shown that there was in fact more consistency than was once thought.

The Big Five
In 1981 in a symposium in Honolulu, four prominent researchers (Lewis Goldberg, Naomi Takamoto-Chock, Andrew Comrey, and John M. Digman) reviewed the available personality tests of the day, and decided that most of the tests which held any promise seemed to measure a subset of five common factors, just as Norman had discovered in 1963.

Emergence of the current model
Following the discovery of the convergence of the Lexical Hypothesis with the findings of theoretical research, a model was developed which states that personality can be described in terms of five aggregate-level trait descriptors.

Although many personality researchers have built their own models, when they talk to each other they usually translate their model into the one proposed by Norman in 1963.

The Factors
(The following descriptions of the five factors were adapted from the writings of Dr. John A. Johnson.)

Extroversion
Extroversion (also sometimes "Extraversion") is marked by pronounced engagement with the external world. Extroverts enjoy being with people, are full of energy, and often experience positive emotions. They tend to be enthusiastic, action-oriented, individuals who are likely to say "Yes!" or "Let's go!" to opportunities for excitement. In groups they like to talk, assert themselves, and draw attention to themselves.

Introverts lack the exuberance, energy, and activity levels of extroverts. They tend to be quiet, low-key, deliberate, and disengaged from the social world. Their lack of social involvement should not be interpreted as shyness or depression; the introvert simply needs less stimulation than an extrovert and prefers to be alone.

Agreeableness
Agreeableness reflects individual differences in concern with cooperation and social harmony. Agreeable individuals value getting along with others. They are therefore considerate, friendly, generous, helpful, and willing to compromise their interests with others'. Agreeable people also have an optimistic view of human nature. They believe people are basically honest, decent, and trustworthy.

Disagreeable individuals place self-interest above getting along with others. They are generally unconcerned with others' well-being, and therefore are unlikely to extend themselves for other people. Sometimes their skepticism about others' motives causes them to be suspicious, unfriendly, and uncooperative.

Agreeableness is obviously advantageous for attaining and maintaining popularity. Agreeable people are better liked than disagreeable people. On the other hand, agreeableness is not useful in situations that require tough or absolute objective decisions. Disagreeable people can make excellent scientists, critics, or soldiers.

Conscientiousness
Conscientiousness concerns the way in which we control, regulate, and direct our impulses. Impulses are not inherently bad; occasionally time constraints require a snap decision, and acting on our first impulse can be an effective response. Also, in times of play rather than work, acting spontaneously and impulsively can be fun. Impulsive individuals can be seen by others as colorful, fun-to-be-with, and zany. Conscientiousness includes the factor known as Need for Achievement (NAch).

The benefits of high conscientiousness are obvious. Conscientious individuals avoid trouble and achieve high levels of success through purposeful planning and persistence. They are also positively regarded by others as intelligent and reliable. On the negative side, they can be compulsive perfectionists and workaholics. Furthermore, extremely conscientious individuals might be regarded as stuffy and boring. Unconscientious people may be criticized for their unreliability, lack of ambition, and failure to stay within the lines, but they will experience many short-lived pleasures and they will never be called stuffy.

Neuroticism or (inversely) Emotional Stability
Neuroticism refers to the tendency to experience negative feelings. Those who score high on Neuroticism may experience primarily one specific negative feeling such as anxiety, anger, or depression, but are likely to experience several of these emotions. People high in Neuroticism are emotionally reactive. They respond emotionally to events that would not affect most people, and their reactions tend to be more intense than normal. They are more likely to interpret ordinary situations as threatening, and minor frustrations as hopelessly difficult. Their negative emotional reactions tend to persist for unusually long periods of time, which means they are often in a bad mood. These problems in emotional regulation can diminish a neurotic's ability to think clearly, make decisions, and cope effectively with stress.

At the other end of the scale, individuals who score low in Neuroticism are less easily upset and are less emotionally reactive. They tend to be calm, emotionally stable, and free from persistent negative feelings. Freedom from negative feelings does not mean that low scorers experience a lot of positive feelings; frequency of positive emotions is a component of the Extroversion domain.

Openness to Experience
Openness to Experience describes a dimension of cognitive style that distinguishes imaginative, creative people from down-to-earth, conventional people. Open people are intellectually curious, appreciative of art, and sensitive to beauty. They tend to be, compared to closed people, more aware of their feelings. They tend to think and act in individualistic and nonconforming ways. People with low scores on openness to experience tend to have narrow, common interests. They prefer the plain, straightforward, and obvious over the complex, ambiguous, and subtle. They may regard the arts and sciences with suspicion, regarding these endeavors as abstruse or of no practical use. Closed people prefer familiarity over novelty; they are conservative and resistant to change.

Openness is often presented as healthier or more mature by psychologists, who are often themselves open to experience. However, open and closed styles of thinking are useful in different environments. The intellectual style of the open person may serve a professor well, but research has shown that closed thinking is related to superior job performance in police work, sales, and a number of service occupations.

Significance
One of the most significant advances of the five factor model was the establishment of a taxonomy that demonstrates order in a previously scattered and disorganized field. For example, as an extremely heterogeneous collection of traits, research had found that "personality" (i.e., any of a large number of hypothesized personality traits) was not predictive of important criteria. However, using the five-factor model as a taxonomy to group the vast numbers of unlike personality traits, psychologists Barrick and Mount used meta-analysis of previous research to show that in fact there were many significant correlations between the personality traits of the five-factor model and job performance in many jobs. Their strongest finding was that psychometric Conscientiousness was predictive of performance in all the job families studied. This makes perfect sense, insofar as it is very difficult to imagine any job where, all other things equal, being high in Conscientiousness is not an advantage.

Scientific findings
Ever since the 1990s when the consensus of psychologists gradually came to support the Big Five, there has been a growing body of research surrounding these personality traits. The existence of each one has been verified by cross-cultural research demonstrating that they exist in individuals outside of Western nations, and all show an influence from both heredity and environment (in roughly equal proportion).

A person's ratings on the five factors has been found to change with time, with Agreeableness and Conscientiousness increasing, while Extroversion, Neuroticism, and Openness generally decrease as a person ages.

Sexes show differences in Big Five scores across cultures, with women scoring higher in both the Agreeableness and Neuroticism domains. (The mere fact that sex differences have been found does not by itself demonstrate that the sexes are innately different in personality, although that is a possibility.)

Individuals also differ when viewed by the order of their births; Frank J. Sulloway has mounted evidence that birth order is correlated with personality traits: firstborns are statistically more conscientious, more socially dominant, less agreeable, and less open to new ideas compared to laterborns.

Recent work has also found relationships between Geert Hofstede's cultural factors, Individualism, Power Distance, Masculinity, and Uncertainty Avoidance, with the average Big Five scores in a country. For instance, the degree to which a country values individualism correlates with its average Extroversion, while people living in cultures which are accepting of large inequalities in their power structures tend to score somewhat higher on Conscientiousness. The reasons for these differences are as yet unknown; this is an active area of research.

Weaknesses
Much research has been conducted into the Big Five. However relatively little of the research has been published in a collated form; most of it appears relatively uncompiled in research journals. For the best understanding of the Big Five, one must be up to date on the literature, which may tend to limit a complete understanding by laypeople.

There are several other weaknesses to the Big Five. The first of these is that the five factors are not fully "orthogonal" to one another; that is, the five factors are not independent. Negative correlations often appear between Neuroticism and Extroversion, for instance, indicating that those who are more prone to experiencing negative emotions tend to be less talkative and outgoing.

Another weakness is that the Big Five do not explain all of human personality. Some psychologists have dissented from the model precisely because they feel it neglects other personality traits, such as:


 * Religiosity
 * Manipulativeness
 * Honesty
 * Sexiness
 * Thriftiness
 * Conservativeness
 * Masculinity/Femininity
 * Snobbishness
 * Sense of humour

Correlations have been found between these factors and the Big Five, such as the well known inverse relationship between political conservatism and Openness, although variation in these traits is not entirely explained by the Five Factors themselves.

Moreover, the methodology used to investigate these phenomena (factor analysis) does not have a well-supported, universally-recognized scientific or statistical basis for choosing among solutions with different numbers of factors. That is, a five factor solution is a choice of the analyst, at least to some degree. A larger number of factors may, in fact, underlie these five factors and a dataset of these variables may be factored into simpler models. This has lead to disputes about the "true" number of factors. Many researchers and practitioners have criticisized these five factors as being far too broad for applied work. In unpublished research, Goldberg (the researcher who coined the term "Big Five") found that Cattell's 16 factor solution has greater predictive power than five factors, even when the number of predictors is controlled by using a cross-validation sample to assess the prediction of competing regression models (16 versus 5 variables).

Another weakness of the Big Five is that they rely on self report questionnaires to be measured; self report bias and falsification of responses is impossible to deal with completely. This becomes especially important when considering why scores may differ between individuals or groups of people - differences in scores may represent genuine underlying personality differences, or they may simply be an artifact of the way the subjects answered the questions.

The last weakness of the Big Five, and a criticism which has frequently been levelled at it, is that it is not based on any underlying theory; it is merely an empirical finding that certain descriptors cluster together under factor analysis. While this does not mean that these five factors don't exist, the underlying causes behind them are unknown. There is no theoretical justification for why sensation seeking and gregariousness are predictive of general Extroversion, for instance; this is an area for future research to investigate.

Further research
Current research concentrates on three areas. The first is: Are the five factors the right ones? Attempts to replicate the Big Five in other countries with local dictionaries have succeeded in some countries but not in others. Apparently, for instance, Hungarians don’t have Openness to Experience. Of course they do, others say, the problem is that the language does not provide enough variance of the related terms for proper statistical analysis. Some have found seven factors, some only three.

The second area is: Which factors predict what? Job outcomes for leaders and salespeople have already been measured, and research is currently being done in expanding the list of careers. There are also a variety of life outcomes which preliminary research indicates are affected by personality, such as smoking (predicted by high scores in Neuroticism and low scores in Agreeableness and Conscientiousness) and interest in different kinds of music (largely mediated by Openness).

The third area is to make a model of personality. The Big Five personality traits are empirical observations, not a theory; the observations of personality research remain to be explained. Costa and McCreae have built what they call the Five Factor Model of Personality which is an attempt to provide a model of personality that can explain personality from the cradle to the grave. They don't follow the lexical hypothesis, though, but favor a theory-driven approach but inspired by the same sources as the sources of the Big Five.