Quantitative Research Methods Lecture 1

what types of evidence do we look at in psych

anecdotal and empirical evidence

anecdotal evidence

evidence drawn from one’s own life or experiences

empirical evidence

evidence based on science, objective and peer reviewed

which evidence do psychologists like the most

empirical evidence

what are the branches in psychology research

quantitative and qualitative research

quantitative research

• maths and statistics

• numbers and data

• objective and generalisation

qualitative research

words, images, observations, focus groups, details understanding

give an example of qualitative research 

interview first year students about their experience of UCT 

give an example of quantitative research

provide 500 students with a survey asking them to rate UCT out of 100

what is involved in psychological research

planning, methods, data collection, data analysis, report findings and theory building

how do you select a topic when planning

• look at everyday life

• identify gaps

• verifying or refuting an existing theory

how do literature reviews guide us when planning 

literature reviews orientate us to what has been found previously, reveals gaps/weakness, reveals methods previously used 

how must you formulate your research question

it must be answerable, ethical and practical

what must you choose in you research methods

designs based on purpose of study and variables of interest, select sample

variables

the things or characteristics we are looking at in our research

independent variable 

influences another variable that is manipulated by researcher

dependent variable

changes in response to independent variable being manipulated

what must you consider when choosing your sample

• who will the participants be

• participants must suit the aim of the study

• sample representative of the population interest

representative sample

group of people selected from a population who have similar characteristics to that population

statistical inference 

process of generalising information obtained from a sample to the whole population 

why is it better to have a bigger sample

there is a greater chance of representing population

name two types of sampling

probability and non-probability sampling

probability sampling is composed of…

simple random and interval sampling

simple random sampling 

assign number to each participant, e.g. draw no. from jar 

interval sampling

• assign number to each participant

• select no. at equal intervals starting at a randomly chosen number

stratified sampling

• divide population into groups

• conduct simple random sampling or interval sampling in each group

multi-stage/cluster sampling

• divide population into clusters

• random select entire clusters to make up the sample

non-probability sampling is composed of…

convenience, purposive and snowball sampling

convenience sampling

select people closest as participants or post an ad and take the first x responders who suit criteria

purposive sampling

researcher uses own judgement to select participants, selecting those who best suit the needs of the study

snowball sampling 

• researcher asks one person to participate 

• that participant is then asked to recruit others who have similar characteristics to themselves