All Rights Reserved.
This work has been summarised from the textbook Psychology: An Introduction
5e, by authors L. Swartz, C. de la Rey, N. Duncan, L. Townsend, V. O’Neill, and
M. Makhubela.
ISBN 9780190748906
It includes notes taken based on lecture slides from relevant topic lecturers, all of
whom are named in the appropriate section. These notes are elaborations based on
the author’s own understanding.
This document, including all content and materials contained within, is the
intellectual property of Arièlle Denis. No part of these notes may be reproduced,
distributed, or transmitted in any form or by any means, including photocopying,
recording, or other electronic or mechanical methods, without the prior written
permission of the author, except in the case of brief quotations embodied in critical
reviews and certain other non-commercial uses permitted by the copyright law.
For permission requests, please contact the author at
© 2025 Arièlle Denis,
University of Cape Town. All rights reserved.
, INTRODUCTION TO PSYCHOLOGY iI
PSY1005S | Term 3
Quantitative Research Methods | Chapter 2 of Swartz et al. textbook
by Sameenah Rawoot
Studying psychology allows us insight into the mind, brain and behaviour. We can understand
ourselves and others, how deviations vary from the baseline or population. We also sharpen our
critical thinking skills and learn to take things not at face-value. We can also, therefore, conduct
research skillfully.
Many of the facts we know to be true or false, such as screen time influencing sleep, or washing
our hands to prevent disease, exist because of research!
Types of evidence
● Anecdotal: Drawn from one’s own life and experience
● Empirical: Based on science, objective and peer-reviewed, with data and references
Branches of Psychological Research
● Qualitative: Words, images, observations, interviews, focus groups
○ Often subjective, summarised and unstructured
● Quantitative: Maths, statistics, numbers and data
○ Often objective, with statistical analysis and structured
e.g. First-year UCT students’ experiences of UCT. Qualitative study would conduct interviews,
while a quantitative study would ask students to rate UCT out of 10.
PROCESS OF QUANTITATIVE RESEARCH
Planning
● Select a topic
○ Relevant to everyday life, workable and useful
○ Can verify or refute an existing theory
○ Identify gaps in previous research
● Review existing literature
○ Orientates the researcher to previous findings
○ Reveals gaps and weaknesses
○ Reveals previous methods
● Formulate a research question
○ Answerable, ethical, practical
, ○ The general problem to be addressed must be formulated, with specific questions
developed
Methods and Methodology
● Design based on the purpose of the study AND the variables of interest – therefore can
select a sample
● Type of study to be considered
○ Exploratory - Very little is known about the research topic
○ Descriptive - Wanting to describe a phenomenon or behaviour
○ Explanatory - Explain the relationship between variables, i.e. correlational or
causational
● Variables:
○ Independent variable: Influences another variable and is manipulated by the
researcher
○ Dependent variable: Changes in response to the independent variable, is
influenced by it and is measured by the researcher
● Sampling
○ Who is involved in the study? Do they suit the aim? Do they represent the
population of interest?
○ Must generalise information from the sample to the entire population
→ Representative sample: A group of people selected from a population who have similar
characteristics to that population.
→ Statistical interference: The process of generalising information from a sample to a whole
population.
A bigger sample means there is a greater chance of representing the population BUT this is more
expensive and has time constraints.
● Probability sampling
○ Simple random sampling – Assign numbers to each participant and draw
randomly
○ Interval sampling – Assign numbers to each participant and select at every
interval
○ Stratified random sampling – Divide people into groups or strata and perform
random or interval sampling in each group for individuals.
○ Multi-stage/cluster sampling – Cluster the sample and randomly pick clusters,
entire groups.
● Non-probability sampling
, ○ Convenience – Use people closest as participants, e.g. posting an advert, or using
the first number of responders who fit the criteria.
○ Purposive – Using your own judgement to see who best suits the needs of the
study.
○ Snowball – One participant recruits others who have similar characteristics.
Sampling affects validity! If you don’t actually look at what you need to, or the sample is not
representative, you risk not being valid. Therefore, this is not a wholly quantitative experience.
● Scientific Method
○ Hypothesis: A statement that indicates what the researcher expects to happen, the
expected outcome. This must be accepted or rejected once tested.
○ Must be proposed based on the research question
■ Experimental hypothesis: What is expected to happen.
■ Null hypothesis: What the researcher is trying to disprove or nullify (e.g.
“Has no effect”, “is not responsible for”)
Data Collection
● Types of studies
○ Cross-sectional study: Data is collected at one point in time, a single instance
○ Longitudinal study: Data is collected over a period of time, at multiple points in
time/instances.
■ Participants can be lost over time, so there is a disadvantage here.
○ What are the units of analysis? How are they chosen?
● Observation
○ Non-participation – observe without interacting with participants
○ Participation – become part of the group while secretly observing
● Interviews
○ General – researcher asks questions and analyses the responses
○ Focus groups – researcher interviews a group rather than individuals one-by-one
● Questionnaires, e.g. Likert scale responses
● Experiments, where one variable is manipulated and another measured
Data Analysis
The method used depends on the nature of the research question and data collected.
Often, descriptive statistics are used, which give a broad overview of the results. This uses
graphs and charts to visualise the observed trends and effects.
This work has been summarised from the textbook Psychology: An Introduction
5e, by authors L. Swartz, C. de la Rey, N. Duncan, L. Townsend, V. O’Neill, and
M. Makhubela.
ISBN 9780190748906
It includes notes taken based on lecture slides from relevant topic lecturers, all of
whom are named in the appropriate section. These notes are elaborations based on
the author’s own understanding.
This document, including all content and materials contained within, is the
intellectual property of Arièlle Denis. No part of these notes may be reproduced,
distributed, or transmitted in any form or by any means, including photocopying,
recording, or other electronic or mechanical methods, without the prior written
permission of the author, except in the case of brief quotations embodied in critical
reviews and certain other non-commercial uses permitted by the copyright law.
For permission requests, please contact the author at
© 2025 Arièlle Denis,
University of Cape Town. All rights reserved.
, INTRODUCTION TO PSYCHOLOGY iI
PSY1005S | Term 3
Quantitative Research Methods | Chapter 2 of Swartz et al. textbook
by Sameenah Rawoot
Studying psychology allows us insight into the mind, brain and behaviour. We can understand
ourselves and others, how deviations vary from the baseline or population. We also sharpen our
critical thinking skills and learn to take things not at face-value. We can also, therefore, conduct
research skillfully.
Many of the facts we know to be true or false, such as screen time influencing sleep, or washing
our hands to prevent disease, exist because of research!
Types of evidence
● Anecdotal: Drawn from one’s own life and experience
● Empirical: Based on science, objective and peer-reviewed, with data and references
Branches of Psychological Research
● Qualitative: Words, images, observations, interviews, focus groups
○ Often subjective, summarised and unstructured
● Quantitative: Maths, statistics, numbers and data
○ Often objective, with statistical analysis and structured
e.g. First-year UCT students’ experiences of UCT. Qualitative study would conduct interviews,
while a quantitative study would ask students to rate UCT out of 10.
PROCESS OF QUANTITATIVE RESEARCH
Planning
● Select a topic
○ Relevant to everyday life, workable and useful
○ Can verify or refute an existing theory
○ Identify gaps in previous research
● Review existing literature
○ Orientates the researcher to previous findings
○ Reveals gaps and weaknesses
○ Reveals previous methods
● Formulate a research question
○ Answerable, ethical, practical
, ○ The general problem to be addressed must be formulated, with specific questions
developed
Methods and Methodology
● Design based on the purpose of the study AND the variables of interest – therefore can
select a sample
● Type of study to be considered
○ Exploratory - Very little is known about the research topic
○ Descriptive - Wanting to describe a phenomenon or behaviour
○ Explanatory - Explain the relationship between variables, i.e. correlational or
causational
● Variables:
○ Independent variable: Influences another variable and is manipulated by the
researcher
○ Dependent variable: Changes in response to the independent variable, is
influenced by it and is measured by the researcher
● Sampling
○ Who is involved in the study? Do they suit the aim? Do they represent the
population of interest?
○ Must generalise information from the sample to the entire population
→ Representative sample: A group of people selected from a population who have similar
characteristics to that population.
→ Statistical interference: The process of generalising information from a sample to a whole
population.
A bigger sample means there is a greater chance of representing the population BUT this is more
expensive and has time constraints.
● Probability sampling
○ Simple random sampling – Assign numbers to each participant and draw
randomly
○ Interval sampling – Assign numbers to each participant and select at every
interval
○ Stratified random sampling – Divide people into groups or strata and perform
random or interval sampling in each group for individuals.
○ Multi-stage/cluster sampling – Cluster the sample and randomly pick clusters,
entire groups.
● Non-probability sampling
, ○ Convenience – Use people closest as participants, e.g. posting an advert, or using
the first number of responders who fit the criteria.
○ Purposive – Using your own judgement to see who best suits the needs of the
study.
○ Snowball – One participant recruits others who have similar characteristics.
Sampling affects validity! If you don’t actually look at what you need to, or the sample is not
representative, you risk not being valid. Therefore, this is not a wholly quantitative experience.
● Scientific Method
○ Hypothesis: A statement that indicates what the researcher expects to happen, the
expected outcome. This must be accepted or rejected once tested.
○ Must be proposed based on the research question
■ Experimental hypothesis: What is expected to happen.
■ Null hypothesis: What the researcher is trying to disprove or nullify (e.g.
“Has no effect”, “is not responsible for”)
Data Collection
● Types of studies
○ Cross-sectional study: Data is collected at one point in time, a single instance
○ Longitudinal study: Data is collected over a period of time, at multiple points in
time/instances.
■ Participants can be lost over time, so there is a disadvantage here.
○ What are the units of analysis? How are they chosen?
● Observation
○ Non-participation – observe without interacting with participants
○ Participation – become part of the group while secretly observing
● Interviews
○ General – researcher asks questions and analyses the responses
○ Focus groups – researcher interviews a group rather than individuals one-by-one
● Questionnaires, e.g. Likert scale responses
● Experiments, where one variable is manipulated and another measured
Data Analysis
The method used depends on the nature of the research question and data collected.
Often, descriptive statistics are used, which give a broad overview of the results. This uses
graphs and charts to visualise the observed trends and effects.