Experimental Design

Question 1

Independent groups/measure design

Answer 1

•two separate groups of pps (each person only takes part in one condition)pps randomly allocated to to conditions to remove bias
•time consuming since 2x number of pps need to be gathered compared to repeated measures
•large numbers of pps means more pp variables affect outcomes
•order effects are avoided since pps only take part in one study

Question 2

Repeated measures

Answer 2

•uses one group of pps who take part in all conditions of a study
Counterbalancing can be used to reduce order effects
•fewer pps are required so impact of pp variables is minimised
•each pp offers more than one piece of data so withdrawals lead to a large loss of data
•can lead to demand characteristics (boardem rehersal)

Question 3

Matched pairs

Answer 3

•two groups but each perosn in one group is matched with someone in the other group
•matched on relevant traits before being randomly allocated to conditions
•pps matched on relevant traits so pp variables are minimised
•time consuming since 2x pps need to be gathered and matched
•order effects are avoided since pps only take part in one condition