experimental design Flashcards
independent groups
two separate groups involved, each group does one of the conditions of the experiment
strength of independent groups
-avoids order effects
-people participating in one condition so they dont get bored doing diff conditions
weakness of independent groups
-more people needed than with repeated measures (confusing)
-differences between individuals in diff groups may affect results
repeated measures
all participants take part in all conditions of the experiment
strength of repeated measures
-reduces participant (extraneous variables)
-avoids order effects so counterbalancing not necessary
weakness of repeated measures
-order effects
-practice effect (knowing what to do)
matched pairs
participants are matched on some variable that is important to experiment then one pair is allocated to diff conditions (twins)
strength of matched pairs
-reduce participant variable
-avoids order effects so counterbalancing not necessary
weakness of matched pairs
-very time consuming to find closely matched pairs
-impossible to match people exactly
random allocation
an attempt to evenly distribute participants across experimental conditions in an independent group design- randomly allocate groups
strength of random allocation
decreases participant variables in the form of individual differences e.g. IQ
weakness of random allocation
not representative
counterbalancing
attempt to control order effects in repeated measures, half do conditions in one order and other half in opposite order
strength of counterbalancing
reduces order effects
weakness of counterbalancing
time consuming
