Research Methods (AQA psychology)

Test of Difference, Independent Measures and Nominal Data

Chi-Squared

Test of Difference, Independent Measures and Ordinal Data

Mann-Whitney

Test of Difference, Independent Measures and Interval/Ratio Data

Unrelated t-test

Test of Difference, Repeated Measures and Nominal Data

Sign Test

Test of Difference, Repeated Measures and Ordinal Data

Wilcoxon

Test of Difference, Repeated Measures and Interval/Ratio Data

Related t-test

Test of Correlation/Relationship and Nominal Data

Chi-square Test

Test of Correlation/Relationship and Ordinal Data

Spearman’s rho

Test of Correlation/Relationship and Interval/Ratio Data

Pearson’s r

Aims

Purpose of the investigation

Hypotheses

Testable, operationalised statement

Directional Hypothesis

A hypothesis which states the direction of the relationship between the variables

Non-directional Hypothesis

A hypothesis which doesn’t state a direction but states that there is a difference

Directional or non-directional

Identifying a difference/corelation or not. Choice depends on previous theory/research

Independent Variable

What is manipulated

Dependent Variable

What is measured

Operationalisation

Defining variables so they can be measured

Extraneous Variables

Nuisance variables but randomly distributed

Confounding variables

Vary systematically with the independent variable

Demand Characteristics

Participants second guess the aims, after their behaviour

Investigator Effects

Influence of researcher on the dependent variable/design decisions

Randomisation

Chance methods to reduce researcher’s bias

Standardiation

Ensuring all participants have the same experience

Independent Groups

Participants in each condition of experiment are different

Repeated Measures

All participants take part in all conditions

Matched Pairs

Similar participants paired on participant variables, allocated condition A or B

Evaluation for Independent Groups

Participant variables aren’t controlled (use random allocation), less economical, no order effects

Evaluation for Repeated Measures

Order effects (use counterbalancing), demand characteristics, participant variables are controlled, more economical

Evaluation for Matched Pairs

No order effects, cannot match participants exactly, time consuming

Laboratory Experiments

The independent variable is manipulated in a controlled setting, participants go to researcher