Extraneous Variable

Standardisation

Experimental Design

Independent groups design

Repeated measures design

Sample

Target population

Representative

Random sample

Opportunity sample

informed consent

Right to withdraw

Confidentiality

Experiment

Lab experiment

Field experiment

Self report

Questionnaire

Closed questions

Open questions

Structured interview

Unstructured interview

Overt observation

Covert observation

Participant observation

Non-participant observation

Case study

Correlation study

Longitudinal study

Cross-sectional study

Validity

Ecological validity

Reliability

Inter-rater reliability

Demand characteristics

Observer effect

Social desirability

Gender bias

Cultural bias

Experimenter bias