Methods of Enquiry in Psychology

The goals and steps of research, kinds of data, observation, experiments and variables, correlation, surveys, tests, case studies, analysis and research ethics.

Key ideas

Research has five goals: description, prediction, explanation, control and application.
It runs in four steps: conceptualising a problem, collecting data, drawing conclusions and revising them.
In an experiment the independent variable is changed by the researcher and the dependent variable is measured; extraneous variables are controlled.
A control group is treated like the experimental group except that the independent variable is absent.
Correlation shows how two variables go together without changing either; it does not prove cause.
A good test is reliable (consistent), valid (measures what it claims) and has norms for comparing scores.
Ethics require voluntary participation, informed consent, debriefing, sharing results and confidentiality.

Remember

Correlation coefficient	from +1.0 (perfect positive) through 0 (none) to −1.0 (perfect negative)
Kinds of data	demographic, physical, physiological, psychological
Controlling variables	elimination, holding constant, matching, counterbalancing, random assignment
Observation	naturalistic or controlled; participant or non-participant
Speed vs power test	time limit, equal items vs no time limit, rising difficulty
Reliability types	test-retest (same test twice); split-half (odd vs even items)

Watch out

Swapping the variables: the cause that is varied is independent, the effect that is measured is dependent.
Reading a strong correlation as proof that one variable causes the other.
Confusing reliability (consistent scores) with validity (measuring the right thing).
Forgetting that psychological scores have no true zero: no one has zero intelligence.

Worked example

Name the independent and dependent variables in the hypothesis “Feedback after each attempt reduces mistakes in learning a dance step”.

Working: the cause that is varied; the effect that is measured

Answer: Independent: feedback after each attempt; dependent: number of mistakes