Not every psychological question can be answered with a true experiment. AQA covers four non-experimental methods.
Observation
Watching and recording behaviour, often in a natural setting. Subtypes:
- Naturalistic — in everyday environments (playground, classroom). High ecological validity; lower control of EVs.
- Controlled — in a lab or set-up. More control; less ecological validity (e.g. Ainsworth's strange situation).
- Covert — participants don't know they're being observed. Reduces demand characteristics; ethical concerns about consent.
- Overt — participants know. Ethical; may produce demand characteristics.
- Participant — observer joins the group (e.g. Festinger's "When Prophecy Fails"). Rich insight; risk of losing objectivity.
- Non-participant — observer remains separate. More objective; less detail.
Use behaviour categories and an observation schedule to standardise what is recorded; use inter-rater reliability (two observers agreeing) to check consistency.
Interview
- Structured: fixed questions, like a spoken questionnaire. Easy to compare answers; lacks depth.
- Unstructured: open conversation. Rich data; hard to compare and analyse.
- Semi-structured: a fixed core plus follow-up probes. Balance of depth and comparability — most common.
Good for subjective experience: depression, social attitudes, life history.
Questionnaire
Written/online questions. Two question types:
- Closed questions (multiple choice, Likert scale) → quantitative data, easy to analyse.
- Open questions ("Describe a time when…") → qualitative data, rich but harder to analyse.
Strengths: scale (thousands of respondents), anonymous, cheap. Weaknesses: response bias (social desirability, acquiescence); literacy required; low return rates; question wording can lead.
Case study
In-depth study of one individual, group or event. Often used for rare conditions (Phineas Gage, H.M., Genie). Methods include interview, observation, psychometric tests, brain scans.
Strengths: detailed insight; can challenge existing theory (e.g. H.M. on memory). Weaknesses: can't generalise from a single case; researcher bias; ethical care needed.
Correlation
Studies the relationship between two variables without manipulating either. Plotted on a scatter diagram; quantified by a correlation coefficient (–1 to +1).
- Positive correlation: as one variable increases, so does the other (e.g. revision time vs grade).
- Negative correlation: as one increases, the other decreases (e.g. screen time vs sleep).
- No correlation: no systematic relationship.
Caution: correlation does not prove causation. A third variable might explain both, or the direction may be reversed.
AI-generated · claude-opus-4-7 · v3-deep-psychology