Coaley, K. (2009): An Introduction to Psychological Assessment and Psychometrics. Sage.
THE ASSESSMENT AND MEASUREMENT OF PERSONALITY
Main questions related to chapter 8:
- How can you distinguish between subjective and scientific views of personality and between situational and dispositional approaches?
- How have psychologists tried to define personality and how is it distinguished from attitudes, interests, values and motivation?
- How do different theoretical approaches try to understand human personality and how do these link with assessment?
- A critical evaluation of personality questionnaires, issues involved and their limitations.
THE CONCEPT OF PERSONALITY
Why do people behave as they do?
”Layman” approaches (Implicit personality theories, Bruner & Taguiri, 1954)
- Often refers to a global implicit jugdment based on all the impressions and feelings created by someone
- Subjective and associated with personal meaning and impressions
- Often a (random/unclear) mix of different aspect
- Mostly based on superficial, casual and chance observations
- Often focuses on the most noticeable characteristics
- Broad generalizations and stereotypes
Scientific approaches (uses empirical methods and aims to be explicit)
- Focuses on objective descriptions
- Includes knowledge about behavioural style, intellectual functioning, motives, attitudes, beliefs and values and their organisation
- Needs to be comprehensive and precise
- Distinguishes between states and traits
Situational and dispositional approaches
- The situational approach views personality as being inconsistent, with behaviour changing across situations and time.
- The dispositional approach views personality as being consistent and unchanging on a trait continuum, with unchanging dispositions regardless of circumstances.
A very difficult task, which many have attempted, resulting in a multitude of different definitions based on different theories. Defining personality is an important matter, because the way we define a concept affects how we investigate it and the results we achieve.
The most commonly quoted definition is probably Allport’s (1937):
Personality is the dynamic organization within the individual of those psychophysical systems that determine a unique adjustment to the environment.
In 1961 he further defined personality as:
The dynamic organization inside the person of psychophysical systems that determine the person’s characteristic pattern of behaviour and thought.
Other attempts as defining personality have often referred to:
- A style or mode of behaviour
- Relatively stable or enduring characteristics enabling prediction
- Adaptation or adjustment to the environment
- Characteristic patterns of behaviour, thinking and feeling
A broad definition could sound something like:
The characteristic, stable patterns of behaviour and modes of thinking and feeling that determine a person’s unique way of adjusting to the environment.
Distinguishing between concepts
- Attitude: A learned disposition to evaluate a stimulus (person, object, issue, event) positively or negatively.
- Interests: A sub-set of a person’s attitudes relating to the (positive) evaluation of personal beliefs.
- Values: The usefulness, importance or worth we attach to activities, objects and how people should behave.
- Motivation: A characteristic consisting of a person’s needs, interests and goals. Focuses on the driving force, its direction and persistence.
THEORIES OF PERSONALITY
Many different theories, views on personality, conceptualizations, assumptions, methods of investigation, different paradigms etc.
- Types vs. traits
Types are simple categories or clusters of traits. Typologies can be misleading as they tend to ignore that characteristics are normally distributed and that it isn’t really possible to divide people into a few categories.
Traits are more capable of measurement, and they form a normally distributed continuum on a scale, having a mean score at the centre. A limitation with using traits is that there are many of them.
- Idiographic vs. nomothetic approaches
Idiographic approaches focus on the unique individual and takes a holistic approach to understanding personality. Data collection would involve ex interviews, observations, Rorschach and Repertory Grid technique. Based on an assumption that people have unique characteristics, and it is therefore difficult to generalize findings to others.
The nomothetic approach focuses on similarities, ex by identifying some attribute and then measuring it within a large group of people, eg by using standardised questionnaires to identify individual differences in the extent of the trait. Based on an assumption that there exists a finite number of variables which account for differences and that these can be described, explained and predicted.
The physiological paradigm
Personality is associated with people’s physiological characteristics.
- Classical typology
Hippocrates suggested that temperament is determined by relative amounts of blood, black bile, yellow bile or mucous, resulting in the four temperaments/types: sanguine, melancholic, choleric and phlegmatic.
- Constitutional typology
Theories which try to link personality with individual physique. Sheldon (1940s) classified body build into 3 somatotypes: endomorphs (skinny and fragile, supposed to display high physiological arousal, social restraint, need for solitude), mesomorphs (athletic and trim, energetic, forceful etc.) and ectomorphs (flabby and plum, sociable, relaxed etc.)
The psychodynamic paradigm
Dynamic interactions between conscious and unconscious psychological drives. Personality is like an iceberg – the conscious mind is the little part above water, while most lies submerged in the unconscious.
- Freud’s psychoanalysis, the id, the ego, the superego. Personality develops through a series of psychosexual stages.
- Other psychodynamic theorists like Adler, Jung, Lacan, Horney, Fromm, Erikson and McDougall.
- Major contribution of psychodynamics lies in its recognition that behaviour is motivated by unconscious needs and conflicts.
- Limitations from an assessment point of view, is that it is difficult to design objective experiments to test Freud’s hypotheses.
- Jungian type theory, based on Jung’s analytical psychology.
- Jung’s conception of personality includes the conscious part of the mind, the personal unconscious and the collective unconscious.
- Individual differences are the result of a fex basic disparities in functioning: introversion/extroversion, sensing/intuition, thinking/feeling and judging/perceiving.
- The MBTI (Myers-Briggs Type Indicator) is based on the disparities above.
The cognitive-behavioural paradigm
Based on social learning theory and classical learning theories. Focuses on scientific methods, thinking in terms of ”cognitive processing”, behaviour patterns, observational learning, how individuals interpret a given situation.
- People: Pavlov, Watson, Skinner, Dollard and Miller, Rotter, Bandura, Mischel.
The phenomenological paradigm
Focus on personal and subjective experiences. Linked to existentialism. Individuals are unique and can be understood in terms of inner experiences. The core of the paradigm = subjectivity.
- The humanistic view (Rogers, Maslow)
Keywords: free will, individual uniqueness, person-centred therapy, positive change and supportive therapy, growth and self-actualisation, brought focus on coss-cultural differences in assessment.
- Personal constructs and the Repertory Grid (Kelly)
Keywords: personal experiences, internal models/constructs, the interpretation of events. The Role Construct Repertory Grid was designed to investigate constructs, focuses on elements in a person’s life, ex the self, other people, objects, events. The person has to sort these elements into categories of personal relevance.
- Murray’s theory of needs
Focus on needs as a driving force. Needs arise in parts of the brain. Personality is a result of the relative amounts of each need and their organisation. Developed the projective assessment method TAT (Thematic Apperception Test).
The biological paradigm
Neuropsychology. Using scientific methods to understand the links between biology, ex the brain, and psychology and behaviour.
- Eysenck’s theory
The brain contains two sets of neural operations, an excitatory and an inhibitory. Different personality traits, ex introversion, extroversion, neuroticism, emotionality, psychopathy, involve different brain processes connected with ex the limbic system, the ARAS (ascending reticular activating system), the ANS (autonomic nervous system) and the SNS (sympathetic nervous system) etc.
- Gray’s theory
Reinforcement sensitivity theory, inspired by Eysenck, connects personality with two brain systems: the Behavioural Approach System (BAS) and the Behavioural Inhibition System (BIS). Focuses on motivation for approaching and avoiding.
- Cloninger’s theory
Linked and related 7 personality domains, 4 temperament domains (ex novelty-seeking and harm avoidance) and 3 character domains (ex self-directedness and cooperativeness) with neurotransmitters in the brain and learning through reward and punishment.
The trait paradigm
Approaches the personality question by separating the concept of personality into different components, ie traits, in order to compare individuals with one another.
- People: Allport, Eysenck (EPI), Cattell (16PF), Costa and McCrae (NEO-PI).
- Assumptions: Our thoughts, feelings and behaviours vary in a number of ways and these variations can be measured. When measured, they are normally distributed, having most people around the average and fewer at the extremes.
- It’s not a theory, it is a system for specifying the components of personality and measuring them. It does not provide explanations for how personality is developed.
- Factor analysis (and lexical analysis (ex NEO-PI)) has been used to identify underlying factors.
- The Big Five: Neuroticism, Extraversion, Openness, Conscientiousness, Agreeableness.
QUESTIONNAIRE-BASED PERSONALITY ASSESSMENT
Some advantages and limitations concerning personality assessment based on questionnaires:
- Self-report data: Depends on personal insight, which is variable.
- Distortion of responses: People may distort or ”fake” responses in order to obtain a desired result. This can be reduced by standardised administration procedures offering feedback, confidentiality and measurement of a person’s test taking style.
- Random responding: Ex when respondents have little motivation for completing a questionnaire. Can be identified by including an infrequency scale (questions that have only one correct answer, and which is usually not noticed if the responder does not read the items carefully).
- Central tendency: A name given to people who consistently choose the middle option. People might be defensive, not wanting to reveal much information about themselves.
- Measurement error
- Correlational approaches to validation: When constructing a correlation matrix, correlations can occur purely by chance depending on sample size. In the case of statistical tests the probability of a significant correlation occuring by chance is less than 5 % or 1 in 20, which means that if a matrix of 20 correlations is constructed using random numbers, one of them has a high probability of being significant purely by chance. (If a matrix has 100 correlations, 5 of them can be accounted for by chance!)