Experimental design Flashcards
What is experimental design?
The different ways in which participants can be organised in relation to the experimental conditions
What are the 3 key types of experimental design?
- Independent groups
- Repeated measures
- Matched pairs
What is the independent groups design?
There are 2 separate groups of participants- one group takes part in condition A, the other takes part in condition B (each group only does ONE condition)
What are the strengths of the independent groups design?
- Order effects are not a problem
- Demand characteristics have less of an influence
What are the limitations of the independent groups design?
- Participant variables not controlled - confounding variables (should use random allocation)
- Less economical- more time and money
What is the repeated measures design?
There is one group of participants. Everyone in the group takes part in BOTH conditions
What are the strengths of the repeated measures design?
- Participant variables controlled
- Fewer participants needed (less time and money)
What are the limitations of the repeated measures design?
- Order effects (should use counterbalancing)
- Demand characteristics feature more
What is the matched pairs design?
Two seperate groups, but people are matched into pairs for shared qualities. ONE of each pair takes part in condition A, and the other takes part in condition B
What are the strengths of the matched pairs design?
- Order effects not a problem
- Less demand characteristics
- Control participant variables (somewhat)
What are the limitations of the matched pairs design?
- Difficult to achieve a perfect match, so some participant variables
- Time consuming and expensive