Experimental design Flashcards
What is experimental design?
The way that the two levels of the IV are delivered.
What are the 3 types of experimental designs?
Repeated measures
Independent group design
Matched pairs design
What are the limitations for a repeated measures design?
More likely to be affected by order effect.
Demand characteristics are high, as when the participants undergo the second test they may guess the purpose of the experiment and change there behavior.
What are the limitations for a independent groups design?
The researcher can’t control the effect of participant variables.
Needs more participants than the repeated measures design in order to end up with the same amount of data (so can be more time consuming and costly).
What are the limitations for a matched pairs design?
It is very time consuming and difficult to match participants on key variables.
It is not possible to control all participant variables.
What are ways of dealing with the limitations of the repeated measures design?
Researcher could use a different test in each round to reduce practice affect.
Or researchers may use counterbalancing in order to avoid participants guessing the aim of the study.
What are ways of dealing with the limitations of the repeated measures design?
Randomly allocate participants to conditions which distributes participant variables.
What are ways of dealing with the limitations of the matched pairs design?
Restrict the number of variables to match the participants on to make it easier and less time consuming.
Perhaps conduct a pilot study in order to highlight which variables are key when matching the participants.
What are the strengths for a repeated measures design?
It is easy and quick to set up.
All the participants (so the same participant variables) experience the same conditions.
What are the strengths for an independent groups design?
Less of a chance for the participants to guess the aims of the experiment (demand characteristics low).
There is no no order effect, so performance is not affected.
What are the strengths for a matched pairs design?
Demand characteristics are low.
More of a chance that participant variables are the same.
What is the definition for counterbalancing?
An experimental technique used to overcome order effects when using a repeated measures design. Makes sure that each condition is tested first or second in equal amounts.
What is the definition for experimental methods?
Procedures used to control the influence of factors such as participant variables in an experiment.
What is the definition for independent groups design?
Participants are split into two groups using random techniques. Each group is then presented with different conditions of the IV.
What is the definition for matched pairs design?
An independent group design, however the pairs of participants are matched according to key variables.
