Experimental Design Flashcards
Define repeated measures design
Each participant takes part in every condition wen each level of the IV
Define independent groups design
Participants are allocated to two (or more) groups representing different levels of IV.
Define matched pair design
Pairs of participants are matched in terms of key, relevant variables. One member of each pair is allocated to one condition and the other is allocated to the other condition.
Limitations of repeated measures design
What are these called?
Practise effects, fatigue effects, boredom effects.
Order effects - extraneous variables arising from the order in which conditions are presented.
How to deal with repeated measures limitations?
How to reduce practise effects?
Counterbalancing ensures that each condition is tested first or second equal amounts.
Use two different, but equivalent, tests to reduce a practise effect
Strengths of repeated measures design
No participant variables
Don’t need as many participants
Limitations of independent groups design
Cannot control the effects of participant variables
Need many participants
How to deal with limitations of independent groups design?
Randomly allocate participants to experimental groups or conditions to distribute participant variables evenly
Limitations of matched pairs design
Time consuming
difficult to match participants on key variables
Not possible to control all participants
How to deal with limitations of matched Pairs design?
Restrict number of variables to match
Conduct a pilot study to consider key variables that might be important
