UNIVERSITY OF SOUTH AFRICA
College of Economic and Management Sciences
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
IOP2606: Industrial and Or-
ganisational Psychology
Assignment 1 — Semester 1, 2026
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
IOP2606
Module Code:
Industrial and Organisational Psychology
Module Name:
Individual Differences, Personality, Biodata
Assignment Topic:
and Learning
[Student Full Name]
Student Name:
[Student Number]
Student Number:
Assignment 1
Assignment Number:
Submitted in partial fulfilment of the requirements for IOP2606 — UNISA 2026
,UNISA | IOP2606 Industrial and Organisational Psychology
Question 1: Individual Differences
Individual differences is a core concept in industrial and organisational psychology. It refers
to the systematic variations among people in terms of their cognitive, affective, and be-
havioural characteristics, and it forms the foundation for understanding why people respond
differently to the same workplace conditions, training programmes, and assessment proce-
dures (Matthews, Dagnall and Lopez Sanchez, 2024). Francis Galton’s pioneering work in
the late nineteenth century on the measurement of human abilities established individual
differences as a formal field of study, and the tradition he established continues to generate
productive empirical research over a century later (Psychology Fanatic, 2022).
1a) Differences Among Individuals in Terms of Thinking, Feeling and Behaving
Personality is most commonly defined as an individual’s consistent patterns of feeling, think-
ing, and behaving (John, Robins and Pervin, 2008, as cited in PSY101 Introduction to Psy-
chology, nd). This definition immediately situates personality within the study of individual
differences: if personality is constituted by patterns that are consistent within a person yet
variable across persons, then the study of personality is precisely the study of how individuals
differ from one another in their characteristic ways of thinking, feeling, and acting.
Differences in thinking (cognition) include variations in how individuals process information,
reason under uncertainty, attend to detail, generate novel ideas, and solve problems. Cog-
nitive styles, creativity, and analytical versus intuitive thinking are all dimensions on which
individuals systematically vary (Psychology Fanatic, 2022). Differences in feeling (affect)
encompass emotional reactivity, emotional regulation, the tendency to experience positive
versus negative affect, and the stable dispositions toward anxiety, optimism, or irritability.
These are captured well by trait dimensions such as Neuroticism (the tendency toward nega-
tive emotionality) and Extraversion (the tendency toward positive, sociable affect) in the Big
Five model (Psychology Today, 2009). Differences in behaving (conduct) include patterns of
interpersonal interaction, conscientiousness in meeting obligations, risk-taking, impulsivity,
and cooperative versus competitive orientations.
The Big Five personality model, also known as the OCEAN model (Openness, Conscientious-
ness, Extraversion, Agreeableness, Neuroticism), provides the most widely researched tax-
onomy of these individual differences in thinking, feeling, and behaving. Research has con-
firmed that the Big Five traits have a heritability of approximately 40 to 50%, are relatively
Page 2 of 21
, UNISA | IOP2606 Industrial and Organisational Psychology
stable across adulthood, and predict a wide range of life outcomes including occupational
performance, relationship satisfaction, and health behaviours (Simply Psychology, 2025;
Pelt, De Vries and Bartels, 2024). Conscientiousness, for instance, reflects differences in the
propensity to be organised, reliable, and goal-directed, and is the single strongest Big Five
predictor of job performance across occupations (Van Beuningen and Verboon, 2025).
Key Distinction
Thinking, Feeling, and Behaving as Distinct but Related Domains: Although the three
domains of thinking, feeling, and behaving are analytically distinct, they are closely
interconnected in personality. A person high in Neuroticism tends to think negatively
about outcomes (cognitive domain), experience heightened anxiety (affective domain),
and avoid challenging situations (behavioural domain). The Big Five traits each carry
implications across all three domains, which is why they have such broad predictive
power for life outcomes.
1b) Differences Among Individuals Conceptually
At the conceptual level, individual differences can be understood through several theoretical
frames. The first is the trait approach, which holds that individuals can be described by a
relatively small number of stable psychological characteristics that manifest consistently
across time and contexts. Trait theories, from Eysenck’s two-factor model through to the
Five-Factor Model, share the premise that traits are internally generated dispositions rather
than responses to situational demands (Wlv.ac.uk, 2022). Hans Eysenck, one of the most
influential contributors to the field, proposed that individual differences in personality have a
biological basis, with each person’s nervous system defining the nature and stability of their
characteristic traits (Wlv.ac.uk, 2022).
The second conceptual frame is the differential psychology perspective, which studies how
and why individuals’ behaviour creates personality differences and the processes that under-
lie those differences (Wlv.ac.uk, 2022). This perspective does not restrict itself to stable traits
but examines the full range of human variation, including intelligence, aptitudes, interests,
values, and motivational dispositions.
The third is the interactionist perspective, which holds that individual differences are not a
property of the person alone but emerge from the interaction between the person’s disposi-
tions and the demands, opportunities, and constraints of the situations they encounter (PMC,
Page 3 of 21
College of Economic and Management Sciences
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
IOP2606: Industrial and Or-
ganisational Psychology
Assignment 1 — Semester 1, 2026
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
IOP2606
Module Code:
Industrial and Organisational Psychology
Module Name:
Individual Differences, Personality, Biodata
Assignment Topic:
and Learning
[Student Full Name]
Student Name:
[Student Number]
Student Number:
Assignment 1
Assignment Number:
Submitted in partial fulfilment of the requirements for IOP2606 — UNISA 2026
,UNISA | IOP2606 Industrial and Organisational Psychology
Question 1: Individual Differences
Individual differences is a core concept in industrial and organisational psychology. It refers
to the systematic variations among people in terms of their cognitive, affective, and be-
havioural characteristics, and it forms the foundation for understanding why people respond
differently to the same workplace conditions, training programmes, and assessment proce-
dures (Matthews, Dagnall and Lopez Sanchez, 2024). Francis Galton’s pioneering work in
the late nineteenth century on the measurement of human abilities established individual
differences as a formal field of study, and the tradition he established continues to generate
productive empirical research over a century later (Psychology Fanatic, 2022).
1a) Differences Among Individuals in Terms of Thinking, Feeling and Behaving
Personality is most commonly defined as an individual’s consistent patterns of feeling, think-
ing, and behaving (John, Robins and Pervin, 2008, as cited in PSY101 Introduction to Psy-
chology, nd). This definition immediately situates personality within the study of individual
differences: if personality is constituted by patterns that are consistent within a person yet
variable across persons, then the study of personality is precisely the study of how individuals
differ from one another in their characteristic ways of thinking, feeling, and acting.
Differences in thinking (cognition) include variations in how individuals process information,
reason under uncertainty, attend to detail, generate novel ideas, and solve problems. Cog-
nitive styles, creativity, and analytical versus intuitive thinking are all dimensions on which
individuals systematically vary (Psychology Fanatic, 2022). Differences in feeling (affect)
encompass emotional reactivity, emotional regulation, the tendency to experience positive
versus negative affect, and the stable dispositions toward anxiety, optimism, or irritability.
These are captured well by trait dimensions such as Neuroticism (the tendency toward nega-
tive emotionality) and Extraversion (the tendency toward positive, sociable affect) in the Big
Five model (Psychology Today, 2009). Differences in behaving (conduct) include patterns of
interpersonal interaction, conscientiousness in meeting obligations, risk-taking, impulsivity,
and cooperative versus competitive orientations.
The Big Five personality model, also known as the OCEAN model (Openness, Conscientious-
ness, Extraversion, Agreeableness, Neuroticism), provides the most widely researched tax-
onomy of these individual differences in thinking, feeling, and behaving. Research has con-
firmed that the Big Five traits have a heritability of approximately 40 to 50%, are relatively
Page 2 of 21
, UNISA | IOP2606 Industrial and Organisational Psychology
stable across adulthood, and predict a wide range of life outcomes including occupational
performance, relationship satisfaction, and health behaviours (Simply Psychology, 2025;
Pelt, De Vries and Bartels, 2024). Conscientiousness, for instance, reflects differences in the
propensity to be organised, reliable, and goal-directed, and is the single strongest Big Five
predictor of job performance across occupations (Van Beuningen and Verboon, 2025).
Key Distinction
Thinking, Feeling, and Behaving as Distinct but Related Domains: Although the three
domains of thinking, feeling, and behaving are analytically distinct, they are closely
interconnected in personality. A person high in Neuroticism tends to think negatively
about outcomes (cognitive domain), experience heightened anxiety (affective domain),
and avoid challenging situations (behavioural domain). The Big Five traits each carry
implications across all three domains, which is why they have such broad predictive
power for life outcomes.
1b) Differences Among Individuals Conceptually
At the conceptual level, individual differences can be understood through several theoretical
frames. The first is the trait approach, which holds that individuals can be described by a
relatively small number of stable psychological characteristics that manifest consistently
across time and contexts. Trait theories, from Eysenck’s two-factor model through to the
Five-Factor Model, share the premise that traits are internally generated dispositions rather
than responses to situational demands (Wlv.ac.uk, 2022). Hans Eysenck, one of the most
influential contributors to the field, proposed that individual differences in personality have a
biological basis, with each person’s nervous system defining the nature and stability of their
characteristic traits (Wlv.ac.uk, 2022).
The second conceptual frame is the differential psychology perspective, which studies how
and why individuals’ behaviour creates personality differences and the processes that under-
lie those differences (Wlv.ac.uk, 2022). This perspective does not restrict itself to stable traits
but examines the full range of human variation, including intelligence, aptitudes, interests,
values, and motivational dispositions.
The third is the interactionist perspective, which holds that individual differences are not a
property of the person alone but emerge from the interaction between the person’s disposi-
tions and the demands, opportunities, and constraints of the situations they encounter (PMC,
Page 3 of 21
