Experimental Methods Flashcards
What is a laboratory experiment
Performed in a controlled environment in which the researcher manipulates the IV and asses the effect on the DV. Standardised procedures are used with participants randomly allocated to groups.
Lab experiment strengths
- High control so easy to replicate.
- High control so able to establish cause and effect.
Lab experiments limitations
- Low ecological validity.
- Participants are likely to display demand characteristics.
What is a field experiment
Occur in real world settings rather than the laboratory. The IV is still manipulated by the experimenter and as many variables as possible are controlled.
Field experiment strengths
- High ecological validity.
- Chance of demand characteristics is reduced.
Field experiments limitations
- Can’t control extraneous variables.
- Participants might not be aware they are taking part- ethical issues
What is a natural experiment
The IV varies naturally; the experimenter doesn’t manipulate it but simply measures the effect on the DV.
Natural experiment strengths
- Gives researchers opportunity to study changes in variables that can’t be manipulated.
- Chance of demand characteristics is reduced.
Natural experiments limitations
- Must wait for the situation to occur naturally.
- Can’t control extraneous variables.
What is a quasi experiment
The IV occurs naturally; the experimenter is unable to change the IV or randomly allocated the participants to conditions.
Quasi experiment strengths
- Give researchers opportunity to study variables that can’t be manipulated.
- Some control over extraneous variables.
Quasi experiment limitations
- Must wait for IV to occur naturally.
- May be difficult to recruit participants.
