research methods Flashcards
what is the purpose of an experiment
to test a cause and effect relationship between variables under controlled conditions
what are the 3 experimental designs
independent groups
matched participants
repeated measures
what is independent groups
each participants is randomly allocated to each group
what is matched participants
each participant is matched with another participant based on one or more personal characteristic that could influence the DV and then one goes in each group
what is repeated measures
each participant is in both groups
what are extraneous variables
any variable other than the IV that may cause a change in the DV
what are confounding variables
any variable other than the IV that has had an unwanted effect of the DV
what are some extraneous and confounding variables
individual participant differences
non standardised procedures
order effects:
- practice effect
- carry-over effect
participant’s expectations
experimenter effect
placebo effect
ways to overcome extraneous and confounding variables
good sampling method and appropriate research design - individual participant differences
standardised instructions - non standardised procedures
counterbalancing - any order effects
single blind study - participant’s expectations
double blind procedure - experimenter effects
placebo - placebo effect
what is counterbalancing
systematically changing the order of treatments or tasks for participants in a balanced way
single blind vs double blind
single blind - only participants don’t know which group they are in
double blind experimenter and participants don’t know which group they are in
sampling methods (3)
random sampling
convenience sampling
stratified sampling
what is allocation
how participants are allocated into each group eg random allocation
depends on experimental design
other types of research
cross sectional study
case study
observational study
self report:
- questionnaire
- interview
- rating scale
types of data (4)
primary data
secondary data
quantitative
qualitative
