Experiments Flashcards
What is the main features of lab ?
-variables are carefully controlled
-the pps are aware that they are taking part in the study -the behaviour may alter
-they have artificial methods and are less like everyday (low in representation and population validity)
What are strengths of lab experiments
They are high in internal validity as the extraneous variables are controlled
-any changes in the DV is due to the IV
What is one weakness of lab experiments
-pps know that they are being studied so may try to find cues about the aims
What is another weakness of lab experiments
-The IV/DV may be operationalised so it doesn’t represent everyday life . Low ecological validity
What is another weakness of lab experiments
They lab experiment has low ecological validity as the PPs may feel uncomfortable and behave differently due to the setting
What are examples of psychological studies (AO2)
Loftus and palmer
Mitral
Moscovi
Peterson and Peterson
What is the main features of a field experiment
-A field is anywhere outside a lab
-the PPs are usually not aware that they are participating in an experiment (behaviour is natural ) - cause and effect
Low in reliability and lacks population/representation validity
What are the strengths of a field studies
-PPs are not awarded that they are being studied so their behaviour is more natural. May not be the case (deep sea divers)
-High in ecological validity
-a field experiment take place in a more natural setting e.g classroom so PPs are relaxed
What are the weaknesses of a field studies
IV may lack mundane realism. Therefore field experiments may not be like everyday life than lab experiments
Difficult to control extraneous variables
Ethical issues-PPs don’t know that they are being studied so it’s difficult to debrief them . Raise ethical issues with manipulating and recording their behaviour
What are the main features of natural experiments
It is not possible for ethical or practical reasons, to deliberately manipulate an IV
The IV varies naturally
The DV may be tested in a lab
E.g Romanian orphans ( institutionalisation)
What are the strengths of a natural experiment
Allows research where the IV can’t be manipulated for ethical or practical reasons
Enables psychologists to study ‘real’ problems such as effects of a disaster
Increased mundane realism and ecological validity
What are the weaknesses of a natural experiments
Cannot demonstrate casual relationships because the IV is not directly manipulated
Random allocation not possible , therefore there be may be confounding variables that cannot be controlled , a threat to internal validity
Can only be used where conditions vary naturally
What is the main features of quasi experiments
The IV is naturally occurring
The DV may be measured in a lab
The IV has not been made to vary be anyone
E.g gender differences
What are the strengths of quasi experiments
Allows comparison between types of people
Carried out in controlled conditions
What are the weaknesses of a quasi experiments
PPs may not be aware of being studied, creating demand characteristics
Reduces internal validity
The DV may be fairly artificial task
