Experimental design Flashcards
What is the independent groups design?
An experimental design where only one participant takes part in only one of the conditions of the experiment
What are the strengths of independent groups design?
There are no order effects
Both conditions tested simultaneously so saves time and effort
Potential investigatory effects and demand characteristics are reduced
What are the limitations of independent groups design?
Participant variables may affect the results
Participants may differ in some crucial way compared to the other group
Twice as many participants are needed
What is repeated measures design?
An experiment where each participant takes part in all conditions of the experiment.
What two processes are used in repeated measures?
Counterbalancing
Randomisation
What is counterbalancing?
A strategy for reducing order effects by ensuring that participant variables occur within equal frequency in all conditions of the experiment
What is randomisation?
The process of using chance to decide the order in which participants experience the experimental or control condition when using a repeated measures design
What are the strengths of repeated measures design?
Uses fewer participants, saving time, effort and money
Participant variables are not a concern
What are limitations of the repeated measures design?
Risk of order effects and because of the need to limit these, the design can be a complex one
Cost of a loss of participants is greater since data for both condition is lost compared to one in independent groups design
What is the matched pairs design?
An experimental design where participants in each condition of the experiment are matched according to important variables
What are the strengths of the matched pairs design?
Good control of participant variables
Eliminates order effects
What are the limitations of the matched pairs design?
Matching participants is very difficult
