Methodology: Participant Designs and Order Effects Flashcards
Define ‘participant design’.
A design which describes how ppts are distributed between experimental conditions.
Define ‘participant variables’.
Variables that create differences in the sample due to ppts individual characteristics.
Give an example of participant variables.
Gender
Define ‘order effects’.
The order of the conditions having an effect on the ppts’ behaviour as a response to it.
Give an example of order effects.
Practise or fatigue in a certain activity.
Define ‘counterbalancing’.
Ppts are separated into different conditions and experience them in a different order from other groups.
Give an example of counterbalancing in psychology.
One group experiencing condition A then condition B compared to another group experiencing condition B then condition A.
Define ‘randomisation’.
Ppts are separated into different conditions and experience them in a completely random order that may differ from the order of another groups.
Give an example of randomisation in psychology.
Ppts in one group experience condition A before B due to a coin toss.
Identify a strength of using counterbalancing/randomisation.
P - High validity
E - It reduces order effects of practise of getting better or fatigue
E - Therefore it wont affect results making more credible
Identify a weakness of using counterbalancing/randomisation.
P - Low reliability
E - Randomising the order conditions are carried out reduces the standardisation of a procedure
E - Therefore it will be harder to replicate and compare if conditions were done in a separate order
State the 3 main participant designs.
1) Independent measures
2) Repeated measures
3) Matched pairs
Define ‘independent measures’.
Ppts take part in only one element of the conditions in an experiment.
Give an example of independent measures in cognitive psychology.
Baddeley (1966) split his 72 volunteers into 4 conditions so that each group only experienced the one condition from: acoustic similarity, acoustic dissimilarity, semantic similarity, and semantic dissimilarity.
Identify 2 strengths of independent measures.
P - No order effects
E - Ppts only experience one condition of the study
E - Therefore there should be no practise or fatigue in an activity that would change behaviour to affect results
P - Less chance of DCs
E - Ppts only experience one condition of the experiment
E - Therefore they are less likely to guess the overall aim
Identify 2 weaknesses of independent measures.
P - Ppt variables can affect results
E - Ppts didn’t take part in all conditions
E - Therefore there may be a large variation between the groups making it less valid to draw conclusions
P - More ppts are needed
E - There needs to be a sufficient amount of ppts to partake in every condition of the experiment
E - As a result this may be more expensive and time consuming
Define ‘repeated measures’.
Every ppt will take part in all elements of the conditions in an experiment.
Give an example of repeated measures in psychology.
Sherif (1954) used repeated measures with all 22 11 year old boys experiencing the 3 conditions: in-group formation, friction phase, integration phase.
Identify 2 strengths of repeated measures.
P - Ppt variables are controlled
E - All ppts take part in every condition and so act as their own control
E - Therefore there are no variations between the conditions as any differences to cancel out making conclusions more valid
P - Doesn’t require as many people
E - You only need one sample to carry out all the conditions
E - Therefore less are required to make sure a condition is represented by enough ppts making it less time consuming and expensive
Identify 2 weaknesses of repeated measures.
P - May suffer from DCs
E - Ppts are taking part in all conditions and so will become familiar with the overall experiment
E - Therefore they may guess the aim and so change their behaviour to what they think the researcher wants
P - May suffer from order effects
E - Ppts take part in all conditions and so may become practised or fatigued in a certain activity
E - Therefore this may affect their behaviour or performance affect validity of results
Define ‘matched pairs’.
All ppts in one of the experimental conditions are matched as closely as possible with a ppt in the other condition.
Give an example of matched pairs in cognitive psychology.
Raine (1997) matched the 41 murderers pleading NGRI to the 41 non-murders based on sex, age, and mental illness (schizophrenia).
Identify 2 strengths of matched pairs.
P - No ppt variables
E - Ppts are paired as closely as possible with a ppt in another condition based on variables they share
E - This therefore controls for differences between the conditions making results more valid
P - No order effects
E - Ppts only experience one condition of the study
E - Therefore there should be no practise or fatigue in an activity that would change behaviour to affect results
Identify 2 weaknesses of matched pairs.
P - More ppts are needed
E - There needs to be a sufficient amount of ppts to match closely to ppts in another condition and if one ppt drops out then 2 pieces of data are lost
E - As a result this may be more expensive and time consuming to gather enough to account for this
P - Matching pairs
E - Testing is rigorous and detailed to match 2 ppts
E - Therefore it can be further time consuming and expensive
