1 - Experimental Methods Flashcards
Define ‘independent variable’
The variable that is manipulated to determine its effect on the dependent variable.
What is a laboratory experiment?
Experiment carried out in a controlled environment
Allows researcher to exert a high level of control over the IV and eliminate any EV.
Can observe and measure change in DV caused by manipulation of IV.
Participants usually randomly allocated.
What are the advantages of a laboratory experiment ?
High level of control = easy to control EV and prevent them becoming CV
IV can be manipulated and so cause and effect relationship between IV and DV can be established
Easily replicated and reliable
What are the disadvantages of laboratory experiments?
Demand characteristics
Lacks mundane realism and ecological validity
What are field experiments?
Carried out in the real world or in a natural setting
IV still manipulated and controlled to see effect on DV
What are the advantages of field experiments?
More mundane realism and ecological validity than in a lab
Cause and effect relationship can be established
Less change of demand characteristics as might not know they are being observed
What are the disadvantages of field experiments?
Less control over EV which could affect DV ( not valid )
Less control over sample
Difficult to replicate
What are Quasi experiments?
Researcher can’t randomly allocate participants to different conditions of the experiment
IV is usually quality of the participant
What is a natural experiment?
Researcher uses naturally occurring IV to see effect on DV
What are the advantages of natural experiments?
High level of mundane realism and ecological validity
Useful when it is impossible or unethical to manipulate IV / sample in a lab or field experiment
What are the disadvantages of natural experiments?
Less control over EV
Difficult to replicate
Difficult to determine cause and effect
Define ‘experimental conditions’
When the independent variable is divided into levels.
Define ‘control condition’
When the independent variable is not manipulated at all. This is to provide a standard against which experimental conditions can be compared to.
Define ‘dependent variable’
The variable that is being measured
Define ‘extraneous variables’
Variables apart from the independent variable that could affect the dependent variable.
