Research methods

Psychology

Psychology

scientific study of behaviour and mental processes

pop psychology

simple and appealing explanations that are not backed up by empirical evidence.

Empirical evidence

evidence that is based on observation, investigation or experiments rather than abstract reasoning

Falsifiable

It is the principle that a proposition or theory can only be considered scientific if in theory it is possible to establish it as false

Replication

Is the process of repeating research to determine the extent to which findings can be generalised

Quantitative Methods

data to characterise behavior is numerical ( numerically expressed laws that characterise behaviour of groups of individuals )

Qualitative methods

data to characterise behaviour is written

Nomothetic approach

a simple set of rules that describes behaviour of all material objects

Variables

a quantity or quality that varies across individuals or situations

operationalised

turning abstract concepts into measurable variables

Constructs

any theoretical defined variable

Hypothesis

statement describing relationship between variables

directional hypothesis

states expect difference to be found between variables

Non-directional hypothesis

states a difference is expected but doesn't implicitly state what it is

anecdotal evidence

evidence that is based only on personal observation (usually collected in a casual or non systematic way )

Independant variable

variable being changed

dependant variable

variable being measured ( expected to change )

correlation

mutual relationship between 2 or more variables

extraneous variables

a variable not being investigated but has the potential to affect the study outcome

co-variables

correlating variables

idiographic approach

in depth approach not seeking to apply universal rules

confounding variables

variable that influences both independant and dependant variable

A sample

A group of individuals taking part in a research study.

Participant

An individual taking part in research.

Sampling

The process of finding and recruiting participants. Different techniques have their own strengths and limitations.

Credibility

The degree to which the results of the research can be trusted.

Generalisability

Extent to which the results/findings of research can be applied outside of the sample.

Bias

If some sort of bias influences the findings it undermines the credibility.

Volunteer sampling

a sample made of only people who choose to partake

Opportunity sampling

A sample of only people who are readily available

Random Sampling

Every person in target population is given the chance to participate

Stratified sampling

a sample which contains representative amounts to your target population

Quota Sampling

Researcher decides how many people should participate and what characteristics they should have before the study begins

Purpose Sampling

Main characteristics are decided but sample size and proportions of characteristics are not

Theoretical Sampling

Stops when data saturation is reached ( type of purporsive )

Snowball Sampling

Participants recruit other participants- usually people in a similar situation

Convenience Sampling

using the easiest available people e.g. uni students not generalisable!

Experimental Study

At least one IV (manipulated) and DV (expected to change)

Correlation Study

No variables are manipulated

Descriptive Studies

Relationships between variables aren't investigated. the interest lies in the distribution of answers

Experimental Designs

the organisation of how one variable is measured and another is manipulated

independent measures design

groups are randomly allocated and compared. the only difference in the groups is how the IV is manipulated

matched pairs design

groups are matched based on the matching variable

repeated measures design

used when comparing conditions rather than group of participants ( the same group will be exposed to 2 or more conditions )

counterbalancing

participants use another group of participants with the conditions in the reverse order

participant variability

difference between groups before experiment begins

matching variable

variable used to organise groups ( controlled variable )

order effects

results could differ depending on what which conditions comes first or due to practise

Data saturation

no new information is obtained from new participants added to the sample

Validity

the extent to which a test measures or predicts what it is supposed to

Construct Validity

Focused on the quality of operationalised constructs

Internal Validity

measures methodological quality of experiment

External Validity

characterises the extent of generalisability ( 2 types )

Population Validity

extent findings can be generalised from sample to target population

Ecological Validity

extent findings can be generalized from experimental setting to external settings

Selection

Occurs if for some reason the groups are not equivalent at the start of the experiment. Apart from the planned IV difference, they differ on some other variable.

History

Refers to outside events that happen to participants in the course of the experiment.

Maturation

During the course of the experiment the participants go through natural developmental processes

Testing effect

The first measurement of the DV may affect the second and any further measurements.

Instrumentation

instrument measuring dv changed slightly between measurements

Regression to the mean

This is a concern when the initial score on the DV is extreme (high or low) and become more average. Way to control this is to have a starting group with the same average starting level

Experimental mortality

some participants drop out during an experiment, which could be a problem if the dropouts are not random.

Demand characteristics

This is where the participant understands the purpose of the experiment and subconsciously changes their behaviour to fit that interpretation. They behave in a way they think the experiment expects.

Experimenter bias

researcher unintentionally exerts an influence on the results of the study. a countermeasure is a double blind design

Quasi Experiment

groups are not randomly allocated but there is a control group

Field Experiments

conducted in real life setting so have high ecological validity but less control over confounding variables

Natural Experiments

conducted in real life settings but researcher does not manipulate IV.

Scatterplot

graphical illustration of data where 1 dot= 1 participant

Correlation

measure of a linear relationship between 2 variables

Negative Correlation

as one score increases the other decreases

Positive correlation

as one score increases so does the other

Zero correlation

scores are not related and no line of best fit can be drawn

Line of best fit

demonstrates a correlation or causation on a graph

Causation

when one variable directly affects another

Statistical Significance

whether or not the difference between groups can be attributed to chance or if the difference is likely the result of experimental influences

Null Hypothesis

no relationship between the two variables

Effect size

absolute value of correlation coefficient ranges from 1 to -1

Triangulation

Different approaches to collecting and interpreting data

Member checking

When data/interpretations and conclusions are shared with participants

Types of Qualitative Research

observation, in-depth interviews, focus groups, case studies, content analysis

Strengths of volunteer sampling

• less likely to be negative

• unlikely to withdraw

Weaknesses of volunteer sampling

• less representative and typically biased

• keen to please which could lead to extraneous variables

Strength and weaknesses of opportunity sampling

• all participants are readily available

• participants are not representative or target population

Strength and weaknesses of Random sampling

• unbiased

• impractical

• no guarantee it is unbiased

Strengths of Stratified sampling

representative and accurate

Limitations of correlational studies

correlation does not equal causation third variable may correlate with both variables and is responsible for correlation curvilinear relationships spurious correlations

What is triangulation?

Different approaches to collecting and interpreting data

Types of Triangulation

method, data, researcher, theory

What is method triangulation ?

Use of multiple methods helps overcome the individual limitations and therefore reinforces the strengths.

• increases the credibility of the study

What is data triangulation?

the use of multiple data sources

• If utilising interviews they should be conducted at different times

What is researcher triangulation ?

A group of researchers as opposed to one researcher is used to conduct the study. This ensures it was not the researcher alone that caused the findings.

What is theory triangulation ?

multiple perspectives or theories are used to interpret the data of the research study.

What does member checking allow ?

allows participants to clarify intentions and correct errors

What are the types of participant bias ?

• Acquiescence bias

• Social desirability bias

• Dominance bias

• Sensitivity bias

What is Acquiescence bias ?

The tendency to agree with items on a questionnaire regardless of the content of the question

What is social desirability bias ?

• Participants tendency to respond or behaviour in way that they think will make them more liked or more accepted.

What is dominant respondent bias ?

occurs in a group interviews setting when one participant influences the behaviours or responses of others in the group

What is sensitivity bias ?

Participants have a tendency to answer regular questions however when it comes to sensitive topics they distort their answers

How to avoid acquiescence bias ?

• avoid asking leading questions

• ask open ending questions

How to avoid social desirability bias ?

Questions should be phrased in a non-judgemental way that suggests that any answer is acceptable