HL psych research methodology

Layla

Independent variable

manipulated factor

dependent variable

measured outcome

controlled variable

kept constant to reduce confounds

Null hypothesis

predicts no effects or difference

sample methods

random, opportunity, volunteer, stratified

Types of Experiments

Lab - in a controlled setting that tests cause-and-effect by manipulating variables., field - in a natural environment that still tests cause-and-effect., true - random assignment that tests cause-and-effect reliably., quasi - without random assignment, so cause-and-effect is less certain.

True Experiments

NEVER prove anything, the goal is to disprove something specifically, the null hypothesis

quasi experiments

do not randomly allocate the participants

Validity

internal validity - how well IV causes DV, external validity - ecological validity + population, construct validity - Does this test really measure what it claims to measure

Bias:

researcher , confirmation , demand characteristics, and social desirability .

Effects

nocebo, placebo, practice, fatigue,

ETHICS IN RESEARCH

CONSENT, WITHDRAW, PROTECTION, CONFIDENTIALITY, DECEPTION, DEBRIEF

ecological validity

how well the findings of a study apply to real-life situations outside the research setting.

causality

causality is when changes in one factor actually produce changes in another.