Transcript Lecture 1 - Psychometric Lab

KV Petrides
Lecture 4
Comparing Theories of Personality
Dr. KV Petrides
www.psychometriclab.com
KV Petrides
Why science?
• There are various methods for acquiring
knowledge. For example:
– Intuition: the act or process of acquiring knowledge without
reasoning or inferring.
– Authority: a basis for accepting information because it is
acquired from a highly respected source.
– Rationalism: the acquisition of knowledge through
reasoning. Reasoning, however, does not always reflect
reality. It is quite possible to reach contradicting conclusions
by means of rational arguments.
– Empiricism: the acquisition of knowledge through personal
experience. “If I have experienced something, then it is valid
and true”.
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What is science?
• The best method for acquiring knowledge is the scientific
method because the information it yields is based as much
as possible on reality.
• Science is a method (a logic of enquiry) to be followed in
solving problems and acquiring a body of knowledge.
• The scientific method comprises the following steps:
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Developing a theory
Forming a hypothesis
Designing an experiment and operationalizing the variables
Conducting the experiment and testing the hypothesis
Interpreting the results
Feeding back and (if necessary) amending the theory
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Assumptions underlying science I
• Reality in nature: What we see, hear, feel, and
taste is real and has substance.
– Empiricism is vital in science, wherein, however, it
refers to accumulation of knowledge through the
scientific method, rather than to personal experiences of
events.
• Rationality: there is a rational basis for the events
that occur in nature, which can be understood
through logical thinking.
– Rationalism is vital in science, however, scientists use
the reasoning process not only to derive hypotheses, but
also to test them.
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Assumptions underlying science II
• Regularity: Events in nature follow the same laws
and occur the same way at all times and places.
• Discoverability: Not only is there uniformity and
regularity in nature, but it is also possible to
discover this uniformity.
• Note that insofar as these assumptions are
incorrect in the realm of personality psychology,
the utility and relative advantages of the scientific
method are compromised.
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Objectives of science
• Description: To portray a situation or phenomenon
accurately and parsimoniously.
• Explanation: To provide an explanation of the
phenomenon or situation, including why it exists
and what causes it.
• Prediction: To enable the anticipation of events
prior to their actual occurrence.
• Control: To manipulate the conditions that
determine a phenomenon. When the antecedent
conditions are known, they can be manipulated to
produce a desired phenomenon.
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Personality theories
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Humanistic and psychodynamic approaches
humanistic
psychodynamic
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Humanistic approach
• This approach has its roots in the philosophical
schools of existentialism and phenomenology.
• It emphasizes that individuals have free will,
personal worth, and a need for self-actualization.
• The main impact of this approach has been in the
areas of clinical psychology and counseling.
• Major figures in the humanistic tradition are Kelly,
Rogers, and Maslow.
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Humanistic approach - Limitations
• Overemphasizes the importance of appreciating
personhood and maintaining close contact with your
feelings.
• Overlooks social and genetic determinants of
personality and being.
• Overemphasizes people’s construal of reality (e.g.,
self-actualization), which makes the theory impossible
to evaluate because there are as many different
construals as there are people.
• Rejects the scientific method as a valid method for
studying the human mind.
– The mind is self-aware and therefore cannot be studied
objectively because it knows it is being studied.
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Psychodynamic approach
• This class of approaches originates from Freud’s
psychoanalytic theory.
• Freudian theory has been highly influential in very
diverse areas of enquiry.
• Today, psychoanalytic theory continues to play an
important role in psychotherapy, although its
influence within mainstream psychology is very
limited.
• Major figures in the psychodynamic tradition are
Freud, Jung, Adler, Horney, and Erikson.
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Psychodynamic approach - Limitations
• Fundamental constructs of the theory are
nebulous (e.g., psychic energy, thanatos, etc.).
• Overemphasizes the importance of sexual
drive and overlooks the role of social and
genetic factors.
• Its clinical effectiveness has been repeatedly
called into question (Eysenck, 1952).
• Theory is so general and vague as to be
untestable and, consequently, unscientific.
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Trait theories
• Trait theories posit that personality is a
constellation of dispositions that influence how
people think, feel, and behave.
• Major advantages of trait theories:
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Predicated on a vast body of empirical evidence.
Explicit, testable, and subject to falsification.
Results and observations are replicable.
Provide useful descriptions and assessment tools for
research and clinical purposes.
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Trait theories - Limitations
• Strong on description and labeling, but often weak
on prediction and, especially, explanation.
• The same variance (factor space) can be
conceptualized in many ways. This is due to the
arbitrariness of factor analysis, which underpins
all hierarchical trait theories.
• Insufficient attention to behavioural variability
across situations (Mischel, 1968).
• Weak on explaining origins of traits.
• Multiple competing theories seemingly enjoying
considerable empirical support.
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Giant 3 vs Big 5
• Giant 3
– H J Eysenck, J A Gray, C R Cloninger, M Zuckerman,
A Tellegen
• Big 5
– P T Costa, Jr & R R McCrae, L R Goldberg, O John
• The study of personality attempts to discover how
people differ and why. Giant 3 theories tend to be
psychobiological and to focus on the why
question. Big 5 theories tend to be descriptive and
to focus on the how question.
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The Giant Three
• H J Eysenck’s
– Extraversion
• The extent to which people prefer to be alone or with others.
– Neuroticism
• The extent to which people experience negative emotions.
– Psychoticism
• The extent to which people are tough-minded.
• J A Gray’s
– Impulsivity (BAS; approach and reward system).
– Anxiety (BIS; inhibition and punishment system).
– Fight/flight (aggression or flight system).
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Advantages of Giant Three theories
• Advantages of Giant Three theories over
Big Five theories:
– Strive to explain WHY individuals differ.
– Attempt to bridge psychology and biology.
– Able to accommodate individual differences not
easily accounted for by environmental
explanations.
– Consistent with animal research findings.
– May be able to support pharmacological
interventions.
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Disadvantages of Giant Three theories
• Disadvantages of Giant Three over Big Five
theories:
– Tend to be less comprehensive. There seems to be
predictively useful personality variance not tapped
by Giant Three models.
– Limited methodology for assessing brain function
and testing the theories.
– Overemphasize biological factors at the expense of
relevant social and cognitive factors.
– Deterministic, allowing little scope for socioeducational interventions (although this may
simply reflect reality).
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The Big Five (FFM)
• Extraversion
– The extent to which people prefer to be alone or with others.
• Neuroticism
– The extent to which people experience negative emotions.
• Agreeableness
– The extent to which people are pleasant and well-liked by
others.
• Conscientiousness
– Concerns the manner in which people complete tasks.
• Openness-to-Experience
– Has been variously described as a dimension of creativity,
culture, curiosity, intellectuality.
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Advantages of Big Five theories
• Advantages of Big Five over Giant Three theories:
– Provide more comprehensive coverage of personality.
– Offer more thorough descriptions and assessments due
to their scope and incorporation of lower-order facets.
– They are perceived as integrative and dominant in the
literature.
• A major advantage, as it facilitates the accumulation of
evidence and provides a reference point for substantive
research.
– O, A, and C have wider nomological networks than P.
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Disadvantages of Big Five theories
• Disadvantages of Big Five over Giant Three theories:
– Psychometric
• The measurement scope and detail of Big Five models mean that
some factors are internally heterogeneous (e.g., facets
correlating more strongly with non-keyed factors than with their
keyed factor).
• Moderate-to-strong factor intercorrelations (e.g., A and C).
– Explanatory
• Especially weak in explaining findings.
• Over-reliant on semantic (thesaurus-based) accounts of
phenomena. Conscientious: competent, dutiful, disciplined, etc.
– Conceptual
• Evidence of factors beyond the Big Five, which is a problem as
regards comprehensiveness.
• Evidence of developmental non-invariance (Mroczek et al.,
1997), which is especially troublesome when origins of factors
are unknown.
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Eysenck versus Gray I
• P-E-N theory advantages:
– Assessment is straightforward (mainly via
questionnaires). In contrast, it is proving difficult to
link BIS and BAS from Gray’s theory to behavioural or
psychometric measures.
– Overall, empirical evidence tends to be somewhat in
favour of Eysenck, but results are often inconclusive or
difficult to replicate (Matthews & Gilliland, 1999).
– Dearth of uncontested and conclusive evidence in
support of Gray’s theory based on human data.
– Eysenckian theory has far wider spheres of influence
and application than Gray’s, which tends to focus on a
relatively small number of specific paradigms.
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Eysenck versus Gray II
• BIS/BAS theory advantages:
– Much more detailed description of physiological
mechanisms than P-E-N model.
– Sometimes impressive evidence from animal
studies (e.g., BIS-based explanations of the effects
of anxiolytic drugs in the rat).
– However, these results do not seem to be replicable
in human samples. It is likely that human anxiety
is much more amenable to cognitive control (selfregulatory processes) than animal anxiety.
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Eysenck versus Gray III
• Because the two theories define the same factor space,
anxiety can be recast as neurotic introversion versus stable
extraversion and impulsivity can be recast as neurotic
extraversion versus stable introversion.
• Decisive factors can be parsimony and explanatory power
(e.g., accuracy of underlying physiological systems).
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On the web
• http://www.personality-project.org/
– Maintained by Professor W. Revelle
• http://freespace.virgin.net/darrin.evans/
– The H J Eysenck official web page
• http://www.cattell.net/devon/rbcmain.htm
– The R B Cattell memorial page
• http://www.spsp.org/
– Society for Personality and Social Psychology