aims hypothesis and variables

aim

a general statement about the purpose of a study

hypothesis

a specific testable prediction about the relationship between variables. must be operationalised

directional(one tailed) hypothesis

predicts a specific direction of effect eg states that one condition will out perform the other

non directional(two tailed) hypothesis

predicts a difference but not direction

null hypothesis

predicts no effect of relationship

there will be NO change

independent variable (IV)

manipulated by the experimenter

dependent variable (dv)

the variable that is measured to determine the outcome of the experiment

extraneous variable

other factors that could affect DV if not controlled eg background noise

confounding variables

variables that vary systematically with IV making results unclear

operationalisation

defining variable in measurable terms eg aggression= number of punches to a doll