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Chapter 8: Traits and Trait Taxonomies
Some psychologists view traits as internal dispositions. Individuals carry the desires, needs, and
wants from one situation to the next. The inner desire influences external behaviour, causing someone to
act a certain way.
Psychologists who view traits as internal dispositions do not equate traits with the external
behaviour in question. For example, if Harry has a strong desire for a hamburger and fries, he also wants
to lose some weight. He refrains from expressing his desire in behavioural terms - he looks at the food
hungrily but resists the temptation to eat it.
The scientific usefulness of viewing traits as causes of behaviour lies in ruling out other causes.
When we say Joan is extraverted because she goes to many parties, we significantrule out all the other
potential reasons for Joan being extraverted.
Other psychologists define traits simply as descriptive summaries of attributes of persons; they
make no assumptions about internality or causality. For example, when we say George is a jealous
person, we say this because George expressed this behaviour. He might have been keeping an eye on his
girlfriend, for instance. This summarises George’s expressed behaviour, yet no assumptions are made
about what causes the behaviour. The trait of jealousy might be internal. However, it could also be
situational. Guys keep flirting with his girlfriend, and she reacts to them.
Several psychologists who endorse the descriptive summary formulation of traits have explored
the implications of this formulation in a program of research called the ‘act frequency approach’. The act
frequency approach starts with the notion that traits are categories of acts. Just as the category ‘birds’ has
specific birds as members of the category, the category of dominance, for example, might include
particular acts such as the following:
● He issued orders that got the group organised.
● She managed to control the outcome of the meeting without the others being aware of it.
● He assigned roles and got the game going.
The act frequency approach to traits consists of three key elements:
● Act nomination: a procedure designed to identify which acts belong in which trait
categories.
● Prototypicality judgement: identifying which acts are most central to or prototypical of
each trait category. For example, which bird do you think of first when thinking about
birds, robins, or penguins?
● Recording act performance: securing the information on the actual performance of
individuals in their daily lives.
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The act frequency approach does not specify how much context should be included in describing
a trait-relevant act. Next to that, the approach applies to overt actions, but what about failures to act and
covert acts that are not directly observable.
The approach can predict important outcomes in everyday life such as job success, salary, and
how rapidly individuals get promoted.
Three important approaches have been used to identify important traits:
● The lexical approach: start with the lexical hypothesis: all-important individual differences have
become encoded within the natural language. Words as reliable and self-centred were invented.
The lexical approach yields two criteria for identifying the important traits-synonym frequency
and cross-cultural universality. The criterion of synonym frequency means that if an attribute has
not merely one or two trait adjectives to describe it but rather many words, then it is a more
important dimension of individual difference. Cross-cultural universality is the second key
criterion of importance within the lexical approach: the more important is an individual difference
in human transactions, the more languages will have a term for it.
● The statistical approach: starts with a pool of personality items. These can be trait words or
questions about behaviour, experience, or emotion. Most researchers using the lexical approach
turn to the statistical approach to distilling self-ratings of trait adjectives into basic categories of
personality traits. Once a large and diverse pool of items has been assembled, the statistical
approach is applied. It consists of having people rate themselves (or others) on the items, then
using a statistical procedure to identify groups or clusters of items. The goals are to identify the
major dimensions of the personality map. Factor analysis is most commonly used in the statistical
approach.
● Theoretical approach: identifying important dimensions of individual differences starts with a
theory determining which variables are important. There is no prejudgement about which
variables are important. The theoretical strategy dictates which variables are important to
measure.
In practice, many researchers use a combination of all three approaches.
Of all taxonomies of personality, the model of Hans Eysenck is most strongly rooted in biology.
He developed a model of personality based on traits that he believed were highly heritable and had a
likely psychophysiological foundation. The three main traits that met these criteria were extraversion-
introversion (E), neuroticism-emotional stability (N), and psychoticism (P), also known as PEN.
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Eysenck’s hierarchical model has each super trait at the top and narrower traits at the second
level. Subsumed by each narrow trait, however, is a third level-that of habitual acts. At the very lowest
level in the hierarchy are specific acts. If enough specific acts are repeated frequently, they become
habitual acts.
There are two biological criteria:
- Heritability: genetic evidence confirms that all three super-traits have moderate
heritabilities.
- Identifiable physiological substrate: one can identify properties in the brain and central
nervous system that are presumed to be part of the causal chain that produces personality
traits.
Wiggins started with the lexical assumption but went further in his effort at taxonomy by arguing
that trait terms specify different kinds of ways in which individuals differ. One kind of individual
difference pertains to what people do to and with each other-interpersonal traits.
The following types of traits specify other kinds of individual differences:
● Temperament traits: such as nervous
● Material traits: such as clingy
● Mental traits: such as clever
● physical traits: such as healthy
Because Wiggings was concerned primarily with interpersonal traits, he carefully separated these
from the other categories of traits. The two resources that define social exchange are love and status.
There are three clear advantages to Wiggins circumplex:
1. It provides an explicit definition of interpersonal behaviour.
2. It specifies the relationships between each trait and every other trait within the model. There are
three types of relationships specified by the model. (1) adjacency, so how close the traits are to
each other in the circumplex and are positively correlated with each other, (2) bipolarity, traits
that are bipolar are located at the opposite sides of the circle and are negatively correlated with
each other, and (3) orthogonality, which specifies that traits that are perpendicular to each other
on the model (at 90 degrees of separation, or right angles to each other) are entirely unrelated to
each other.
3. It alerts investigators to gaps in investigations of interpersonal behaviour.
The big five has been the taxonomy of personality traits that have gotten the most attention. It
consists of (1) extraversion, (2) agreeableness, (3) conscientiousness, (4) emotional stability, and (5)