AQA AS Psychology A - Research Methods

Hypothesis

A precise, testable statement about the expected outcome of an investigation.

Aim

A general statement about the purpose of the investigation. 

Experiment

A research investigation in which one specific variable is manipulated to observe its effect on another specific variable, while keeping all other variables controlled. In a true experiment participants are randomly allocated to conditions or take part in all. 

Variable

A measureable characteristic or value that can differ from one person to another or have multiple values. 

Experimental Hypothesis

A hypothesis used in the context of an experiment.

Alternative Hypothesis

Any hypothesis that is not the null.

Correlational Study

An investigation into the possible association of two variables.

Operationalising

The process of devising a way of measuring a variable. 

Internal Validity

A research study or experiment has internal validity if the outcome is the result of the variables that are manipulated in the study.

External Validity

The extent to which findings can be generalised to settings other than the research setting.