Lesson 1 - Experimental Methods Flashcards
What is the independent variable?
It’s the variable that the researcher manipulates in order to see its effects on the dependant variable.
What is the dependant variable?
The variable that is being measured
What are confounding variables?
Variables that interfere with the measuring of the dependant variable, eg time of day
What are extraneous variables?
Any other variable that can effect the DV other than the IV, eg age, IQ
What is a laboratory experiment?
It is where the researcher directly manipulates the IV in order to see its effect on the DV which takes place in a highly controlled environment
Strengths of a laboratory experiment?
- High level of control
- Possible to replicate the experiment
- Cause and effect can be determined
Weaknesses of laboratory experiments?
- Setting is not real, so lacks ecological validity and mundane realism
- Chance of demand characteristics
What is a field experiment?
Where experimenters directly manipulates the IV to see the effect on the DV in a natural setting
Strengths of a field experiment?
- Higher ecological validity than a laboratory experiment.
- Lower chance of demand characteristics.
- Cause and effect can be determined
Weaknesses of field experiments?
- Less control over EV
- Less control of sample
- Difficult to replicate
What is a natural experiment?
Where the researcher takes advantage of a naturally occurring IV to see the effect on the DV
Strengths of natural experiments?
- High ecological validity
- Useful when it is impossible or unethical to manipulate IV in any other setting.
Weaknesses of natural experiments?
- Less control over EV
- Difficult to replicate
- Far more difficult to determine cause and effect
What is a quasi experiment?
Very similar to a natural experiment, in that the IV is not directly manipulated, however are generally carries out in a lab setting.
Eg: a variable that cannot be directly manipulated but still can be carried out in a lab setting is gender; to test gender differences in memory.
Strengths of a quasi experiment?
- Control -> the effects of extraneous variables are minimised
- High replication -> strict control makes it easier to replicate
