414 Part V Biological/Evolutionary Theories
Criteria for Identifying Factors
With these assumptions in mind, Eysenck listed four criteria for identifying a fac-
tor. First, psychometric evidence for the factor’s existence must be established. A
corollary to this criterion is that the factor must be reliable and replicable. Other
investigators, from separate laboratories, must also be able to find the factor, and
these investigators consistently identify Eysenck’s extraversion, neuroticism, and
psychoticism.
A second criterion is that the factor must also possess heritability and must fit
an established genetic model. This criterion eliminates learned characteristics, such as
the ability to mimic the voices of well-known people or a religious or political belief.
Third, the factor must make sense from a theoretical view. Eysenck employed
the deductive method of investigation, beginning with a theory and then gathering
data that are logically consistent with that theory.
The final criterion for the existence of a factor is that it must possess social
relevance; that is, it must be demonstrated that mathematically derived factors have
a relationship (not necessarily causal) with such socially relevant variables as drug
addiction, proneness to unintentional injuries, outstanding performance in sports,
psychotic behavior, criminality, and so on.Hierarchy of Behavior Organization
Eysenck (1947, 1994c) recognized a four-level hierarchy of behavior organization.
At the lowest level are specific acts or cognitions, individual behaviors or thoughts
that may or may not be characteristic of a person. A student finishing a reading
assignment would be an example of a specific response. At the second level are
the habitual acts or cognitions, that is, responses that recur under similar condi-
tions. For example, if a student frequently keeps at an assignment until it is fin-
ished, this behavior becomes a habitual response. As opposed to specific responses,
habitual responses must be reasonably reliable or consistent.
Several related habitual responses form a trait—the third level of behavior.
Eysenck (1981) defined traits as “important semi-permanent personality disposi-
tions” (p. 3). For example, students would have the trait of persistence if they
habitually complete class assignments and keep working at other endeavors until
they are finished. Although traits can be identified intuitively, trait and factor
theorists rely on a more systematic approach, namely factor analysis. Trait-level
behaviors are extracted through factor analysis of habit-level responses just as
habitual responses are mathematically extracted through factor analysis of specific
responses. Traits, then, are “defined in terms of significant intercorrelations between
different habitual behaviors” (Eysenck, 1990, p. 244). Most of Cattell’s 35 normal
and abnormal primary source traits are at this third level of organization, which
accounts for the fact that he identified far more personality dimensions than either
Eysenck or advocates of the Five-Factor Theory (see Chapter 13).
Eysenck concentrated on the fourth level, that of types or superfactors. A
type is made up of several interrelated traits. For example, persistence may be
related to inferiority, poor emotional adjustment, social shyness, and several other
traits, with the entire cluster forming the introverted type. Each of the four levels
of behavior organization are shown in Figure 14.1.