Individual differences = psychology of a person, between people and their similarities
PERSONALITY
Implicit personality theories:
What we do when we people watch and talk about people
Intuitively based and unconscious
We all do it – helps to understand ourselves and other people
Making judgements whether we are aware of it or not
observations -> implicit theories -> behavioural prediction
Problems with implicit theories:
Evidence
o Not systematically done
o Not scientific
o Just what we think and feel
Casual, non random observations
Environment influenced by you
Confirmatory bias (stick to what we know in our heads and only accept supporting information)
Defining personality – a precise definition is needed for effective measurement.
Lay definitions:
Involve value judgements within a social context
Often linked to implicit personality
Folklore, linking physical attributes to personality
Include relational evaluations and judgements
Psychological definitions:
No single agreed upon definition
Characteristics/qualities that are typical of an individual
Maltby et al., 2013
o Personality “describes a psychological construct that is a mental concept that influences
behaviour via the mind-body interaction”
Allport, 1961
o Personality is a “dynamic organisation inside the person, of psychophysical systems that
create the person’s characteristic patterns of behaviour, thoughts and feelings”
Psychophysical system = inclusion of both our minds and our bodies in what we refer to as personality.
Why study personality:
Explain motivational basis of behaviour
Ascertain basic nature of human beings
Understand personality development
Understand mental illness and abnormal behaviour
Heritability vs environment (nature-nurture debate)
Provide descriptions and categorisations of how individuals behave
Facilitate behaviour change
Measure personality
Personality can be studies using the idiographic approach or the nomothetic approach:
Idiographic
Focuses on the individual (unique-ness)
, Describe personality variables within that individual
Each individual has a unique personality structure (infinite)
Nomothetic
Focus on the finite number of personality variables
Occurring consistently across groups of variables
Individual is located within this set of variables
Idiographic Nomothetic
Research strategy emphasises uniqueness of Research strategy focuses on similarities
individual between groups and unique combination of
Goal is to develop an in depth understanding traits
of the individual Goal is to identify basic structure and simplicity
Qualitative research methods (case studies, to describe a person
cross study comparisons) Quantitative research method, look at
Diary studies, interviews, therapy sessions etc. relationships between variables
Gain an in depth understanding Self report, personality questionnaires
Difficulties in generalisation Allow general principles and a predictive value
Only a superficial understanding of individuals
Basic criteria personality theories should satisfy:
Description – identify, simplify, clarify
Explanation – why
Empirical validity – generate predictions
Testable concepts – allow reliable empirical investigation
Comprehensiveness – include both normal/abnormal behaviour
Parsimony – conceptual economy (simple and focused)
Heuristic value – stimulates research
Applied value – practical usefulness
Roberts et al., 2007, Power of Personality
Ability to predict important life outcomes from personality is questioned due to the small effects it
has
Predictive validity of personality traits compared with socioeconomic status (SES) and cognitive
ability to test relative contribution of personality traits to predictions of mortality, divorce, and
occupational attainment
Meta analysis of longitudinal studies
Found personality traits to influence life outcomes, therefore we need to incorporate measures of
personality into quality of life surveys – encourage more research about developmental origins of
personality traits and processes by which these influence life outcomes
Found personality to impact mortality, divorce, and occupational attainment the same as
socioeconomic status and cognitive ability
Some studies indicated that personality traits like conscientiousness predicted occupational and
marital outcomes more so
o Generally other factors linked
o Synergistic factors and relations between personality traits and social environmental
factors
o People with positive personality traits generally lived longer
Traits:
People like to assign traits to themselves and others, it is instinctive.
Burger (1997) – “a trait is a dimension of personality used to categorise people according to the degree
to which they manifest a particular characteristic”
,Mischel (1999) – “a trait is a conditional probability of a category of behaviours in a category of contexts”
Conditional probability = likelihood, something you can calculate
Assumptions – stable traits over time, and context (once your personality is developed over like 5 years or
so, it is fixed). This is rooted into the nomothetic approach.
Sheldon’s Somatypes Theory (1970):
Idea you can categorise people by their body types
Personality and body type go hand in hand
Based on early constitutional approach, work of Krestchmer
Perceptions of somatypes (Rychman et al., 1989)
Intuitive links between body type and what people think of personality
Gives some weak evidence for the theory but tells you more about our cultural norms and what we
think of and value in society
E.g. ectomorph – intelligent but fearful
o Mesomorph – hardworking and popular
o Endomorph – slow, sloppy and lazy
Physique Temperament
Focus on part of Physique Temperament Description
body
Ectomorph Nervous system Light boned with Cerebrotonia Need for privacy,
and brain slight musculature restrained, and
inhibited
Mesomorph Musculature and Large, bony with Somatotonia Physically
circulatory system well defined assertive,
muscles competitive, keen
on physical activity
Endomorph Digestive system, Rounded body, Visceratonia Associated with a
particularly tend towards love of relaxation
stomach fatness and comfort like
food and are
sociable
The lexical hypothesis – Galton, 1884
Important useful descriptors of humans will be encoded in language as single terms
The frequency of the descriptor in a language denotes how important it is (and the number of
synonyms it has)
Personality descriptor Number of synonyms
Important Honest 31
Warm 13
Pedantic 9
Unimportant Aberrant (odd/peculiar) 0
Allport – lexical researchers are limited to counting terms, identifying synonyms and producing lists
Allport and Odbert (1936) – identified 18 000 words, 4 500 of which described personality traits
Allport, 1961
Distinction between nomothetic and idiographic
o Common personality traits
o Personal disposition
Came up with personality trait ideas
, o Cardinal traits = single dominating trait of a person e.g. competitiveness
o Central traits = 5-10 best descriptor of a person
o Secondary traits = preference rather than a core constituent of a person at an individual
level
Proprium – a synonym for self, representing all parts, comprising a concept of self. Challenge to
psychology.
Cattell
Overview -> applied empirical methods to discover basic structure of personality.
Process -> large samples of individuals asked to rate degree to which attributes apply to them. “Social
desirability” etc. may have occurred but effects “washed out” by large volume of data collected.
Underwent factor analysis, statistical identification of clusters, correlated items
e.g. achievement oriented people – determined, persistent, productive, goal directed.
Catell (1965) definition of personality – the characteristics of the individual that will allow prediction of
how they will behave in a given situation.
Cattell (1965) Types of Traits:
Ability traits
Dynamic traits
Temperament traits
Environmental – mould traits (nurture)
Constitutional traits (nature, genes)
Unique traits (personal)
Common traits (classify and compare between people)
Surface traits – collections of trait descriptors that cluster together in many individuals and situations
Source traits – represent underlying structure of personality, responsible for the observed variation in
surface traits
If extraversion was a source trait, the surface traits would be sociable, carefree, hopeful, contented.
Cattell and Kline (1977)
Looked at Allport and Odberts (1936) list and reduced it to 171 words describing personality
Raters removed synonyms, and independent people checked
Also reviewed research, personality assessment and psychiatric literature
Then reduced to 46 surface traits that are believed to be sufficient to describe individual
differences in personality
Collected a huge data set comprising:
L-data – life record data e.g. how many times they were married, how many years of education
Q-data – questionnaire data, e,g, how much does this apply to me
T-data – test completion under standard conditions
Surface to source traits – factor analysis of 46 surface traits, 16 major source factors identified, ranked by
factor importance in predicting behaviour (Cattell, Eber, and Tatsuoka, 1970).
1. Outgoing/reserved
2. Intelligence
3. Stable/emotional
4. Assertive/humble
5. Happy-go-lucky/sober
6. Conscientious/expedient
7. Venturesome/shy
PERSONALITY
Implicit personality theories:
What we do when we people watch and talk about people
Intuitively based and unconscious
We all do it – helps to understand ourselves and other people
Making judgements whether we are aware of it or not
observations -> implicit theories -> behavioural prediction
Problems with implicit theories:
Evidence
o Not systematically done
o Not scientific
o Just what we think and feel
Casual, non random observations
Environment influenced by you
Confirmatory bias (stick to what we know in our heads and only accept supporting information)
Defining personality – a precise definition is needed for effective measurement.
Lay definitions:
Involve value judgements within a social context
Often linked to implicit personality
Folklore, linking physical attributes to personality
Include relational evaluations and judgements
Psychological definitions:
No single agreed upon definition
Characteristics/qualities that are typical of an individual
Maltby et al., 2013
o Personality “describes a psychological construct that is a mental concept that influences
behaviour via the mind-body interaction”
Allport, 1961
o Personality is a “dynamic organisation inside the person, of psychophysical systems that
create the person’s characteristic patterns of behaviour, thoughts and feelings”
Psychophysical system = inclusion of both our minds and our bodies in what we refer to as personality.
Why study personality:
Explain motivational basis of behaviour
Ascertain basic nature of human beings
Understand personality development
Understand mental illness and abnormal behaviour
Heritability vs environment (nature-nurture debate)
Provide descriptions and categorisations of how individuals behave
Facilitate behaviour change
Measure personality
Personality can be studies using the idiographic approach or the nomothetic approach:
Idiographic
Focuses on the individual (unique-ness)
, Describe personality variables within that individual
Each individual has a unique personality structure (infinite)
Nomothetic
Focus on the finite number of personality variables
Occurring consistently across groups of variables
Individual is located within this set of variables
Idiographic Nomothetic
Research strategy emphasises uniqueness of Research strategy focuses on similarities
individual between groups and unique combination of
Goal is to develop an in depth understanding traits
of the individual Goal is to identify basic structure and simplicity
Qualitative research methods (case studies, to describe a person
cross study comparisons) Quantitative research method, look at
Diary studies, interviews, therapy sessions etc. relationships between variables
Gain an in depth understanding Self report, personality questionnaires
Difficulties in generalisation Allow general principles and a predictive value
Only a superficial understanding of individuals
Basic criteria personality theories should satisfy:
Description – identify, simplify, clarify
Explanation – why
Empirical validity – generate predictions
Testable concepts – allow reliable empirical investigation
Comprehensiveness – include both normal/abnormal behaviour
Parsimony – conceptual economy (simple and focused)
Heuristic value – stimulates research
Applied value – practical usefulness
Roberts et al., 2007, Power of Personality
Ability to predict important life outcomes from personality is questioned due to the small effects it
has
Predictive validity of personality traits compared with socioeconomic status (SES) and cognitive
ability to test relative contribution of personality traits to predictions of mortality, divorce, and
occupational attainment
Meta analysis of longitudinal studies
Found personality traits to influence life outcomes, therefore we need to incorporate measures of
personality into quality of life surveys – encourage more research about developmental origins of
personality traits and processes by which these influence life outcomes
Found personality to impact mortality, divorce, and occupational attainment the same as
socioeconomic status and cognitive ability
Some studies indicated that personality traits like conscientiousness predicted occupational and
marital outcomes more so
o Generally other factors linked
o Synergistic factors and relations between personality traits and social environmental
factors
o People with positive personality traits generally lived longer
Traits:
People like to assign traits to themselves and others, it is instinctive.
Burger (1997) – “a trait is a dimension of personality used to categorise people according to the degree
to which they manifest a particular characteristic”
,Mischel (1999) – “a trait is a conditional probability of a category of behaviours in a category of contexts”
Conditional probability = likelihood, something you can calculate
Assumptions – stable traits over time, and context (once your personality is developed over like 5 years or
so, it is fixed). This is rooted into the nomothetic approach.
Sheldon’s Somatypes Theory (1970):
Idea you can categorise people by their body types
Personality and body type go hand in hand
Based on early constitutional approach, work of Krestchmer
Perceptions of somatypes (Rychman et al., 1989)
Intuitive links between body type and what people think of personality
Gives some weak evidence for the theory but tells you more about our cultural norms and what we
think of and value in society
E.g. ectomorph – intelligent but fearful
o Mesomorph – hardworking and popular
o Endomorph – slow, sloppy and lazy
Physique Temperament
Focus on part of Physique Temperament Description
body
Ectomorph Nervous system Light boned with Cerebrotonia Need for privacy,
and brain slight musculature restrained, and
inhibited
Mesomorph Musculature and Large, bony with Somatotonia Physically
circulatory system well defined assertive,
muscles competitive, keen
on physical activity
Endomorph Digestive system, Rounded body, Visceratonia Associated with a
particularly tend towards love of relaxation
stomach fatness and comfort like
food and are
sociable
The lexical hypothesis – Galton, 1884
Important useful descriptors of humans will be encoded in language as single terms
The frequency of the descriptor in a language denotes how important it is (and the number of
synonyms it has)
Personality descriptor Number of synonyms
Important Honest 31
Warm 13
Pedantic 9
Unimportant Aberrant (odd/peculiar) 0
Allport – lexical researchers are limited to counting terms, identifying synonyms and producing lists
Allport and Odbert (1936) – identified 18 000 words, 4 500 of which described personality traits
Allport, 1961
Distinction between nomothetic and idiographic
o Common personality traits
o Personal disposition
Came up with personality trait ideas
, o Cardinal traits = single dominating trait of a person e.g. competitiveness
o Central traits = 5-10 best descriptor of a person
o Secondary traits = preference rather than a core constituent of a person at an individual
level
Proprium – a synonym for self, representing all parts, comprising a concept of self. Challenge to
psychology.
Cattell
Overview -> applied empirical methods to discover basic structure of personality.
Process -> large samples of individuals asked to rate degree to which attributes apply to them. “Social
desirability” etc. may have occurred but effects “washed out” by large volume of data collected.
Underwent factor analysis, statistical identification of clusters, correlated items
e.g. achievement oriented people – determined, persistent, productive, goal directed.
Catell (1965) definition of personality – the characteristics of the individual that will allow prediction of
how they will behave in a given situation.
Cattell (1965) Types of Traits:
Ability traits
Dynamic traits
Temperament traits
Environmental – mould traits (nurture)
Constitutional traits (nature, genes)
Unique traits (personal)
Common traits (classify and compare between people)
Surface traits – collections of trait descriptors that cluster together in many individuals and situations
Source traits – represent underlying structure of personality, responsible for the observed variation in
surface traits
If extraversion was a source trait, the surface traits would be sociable, carefree, hopeful, contented.
Cattell and Kline (1977)
Looked at Allport and Odberts (1936) list and reduced it to 171 words describing personality
Raters removed synonyms, and independent people checked
Also reviewed research, personality assessment and psychiatric literature
Then reduced to 46 surface traits that are believed to be sufficient to describe individual
differences in personality
Collected a huge data set comprising:
L-data – life record data e.g. how many times they were married, how many years of education
Q-data – questionnaire data, e,g, how much does this apply to me
T-data – test completion under standard conditions
Surface to source traits – factor analysis of 46 surface traits, 16 major source factors identified, ranked by
factor importance in predicting behaviour (Cattell, Eber, and Tatsuoka, 1970).
1. Outgoing/reserved
2. Intelligence
3. Stable/emotional
4. Assertive/humble
5. Happy-go-lucky/sober
6. Conscientious/expedient
7. Venturesome/shy
