year 1 summary
experimental method
aim - general statement describing purpose of investigation
hypothesis - statement stating the relationship between variables
directional - states a clear difference anticipated between two conditions/groups (used when there’s previous research)
non-directional - states an unspecified difference (used when there’s no previous research)
null - states there is no difference
independent variable - what is changed/manipulated
dependent variable - experiences effect of changing IV
operationalising - making a variable measurable (must be in hypothesis)
variables
extraneous variables - other variables that may interfere with the IV (should be controlled/removed)
confounding variables - other variables that may interfere with the IV and can’t be controlled
demand characteristics - cues from the researcher or experiment that may reveal the purpose (change behaviour accordingly)
investigator effects - unwanted influence that the investigator has on the research outcome (control using randomisation)
standardation - list of exact study procedure so that non-standardised changes don’t act as the extraneous variable
experimental design
IG - two separate groups of participants (often if there are diff levels of IV) (no order effects/ demand characteristics)
RM - same groups experience both conditions (no confounding variables)
MP - participants of each condition paired together based on chosen variables (controls confounding variables)
counterbalancing (used in RM) - diff participants have a switched order of conditions
types of experiment
lab - high controlled environment
strength - controls EV, can replicate study
limitation - low external validity, demand characteristics