Research Methods 3+4: Experimental Design Flashcards
Experimental design refers to…
Different ways in which participants can be organised in relation to the experimental conditions.
3 experimental designs are…
Repeated measures design, Independent groups design, Matched pairs design
Independent groups advantage: order effects
Order effects are avoided as participants only take part in one condition. Strength because it increases internal validity.
Independent groups advantage: demand characteristics
Less like to be affected by demand characteristic cos they only take part in one condition so are exposed to less cues. Strength cos it increases internal validity.
Independent groups advantage: resources
Same resources can be used as there’s a different participant in each condition so all participants are exposed to equal materials. Strength cos it increases internal validity.
Independent groups limitation: time consuming
Different participants in each condition means having to find more participants. Limitation cos it’s more time consuming to gather the sample.
Independent groups limitation: participant variables
Different participants in each condition so DV may be influenced by participant variables rather than the IV. Limitation cos it reduces internal validity.
Repeated measures strengths: participant variables
Same participant does both conditions so there’s no participant variables. Strength cos increases internal validity.
Repeated measures strengths: less time consuming
Participant does both conditions so don’t have to find as many participant. Strength cos it saves the researcher time and money.
Repeated measures limitation: demand characteristics
Same participant used in both conditions means exposed to more cues so more likely to be affected by demand characteristic. Limitation cos it reduces internal validity.
Repeated measures limitations: resources
Participant doing both conditions means resources can’t be reused so participants maybe not exposed to equal materials. Limitation cos it reduces internal validity.
Repeated measures limitations: time consuming
Same participant for both conditions means can’t be tested at the same time. Limitation cos it takes more time to carry out the experiment.
Repeated measures limitations: order effects
Same participant for both experiment means they may have an improved/reduced performance in the second condition. Limitation cos it decreases internal validity.
Matched pairs strengths: participant variables
Participants are matched on important variables so difference in the DV is unlikely to be from participant variables. Strength cos increases internal validity.
Matched pairs strengths: order effects
Participants only take part in one experiment so order effects are avoided so performance in one condition won’t improve/decrease. Strength cos increases internal validity.
Matched pairs strengths: demand characteristics
Only take part in one condition so exposed to less cues. Strength cos it increases internal validity.
Matched pairs strengths: resources
Only take part in one condition so resources can’t be reused and equal for all participants. Strength cos it increases internal validity.
Matched pairs limitations: time consuming
Difficult to match pairs cos tests are done to match participants with similar important variables. Limitation cos it’s very time consuming and expensive.
Randomisation is…
The use of chance methods to control for the effects of bias when designing materials and deciding on the order of the conditions in an experiment.
Counterbalancing is…
An attempt to control for the effects of order effects in a repeated measures design: half of participants experience one conditions first other half experience other condition first.
Random allocations is…
An attempt to control for participant variables in an independent groups design ensuring that each participant has the same chance of being in one condition as any other.
Standardisation is…
Ways in which procedures/materials within an investigation are kept the same for all participants. All should have the same experience.
