RM - Experiment types Flashcards
What is a laboratory experiment?
Carried out in a v. controlled environment like a lab or classroom. Experimenter manipulates IV and there is strict control over extraneous variables. Records DV.
What is a field experiment?
Carried out in the participants natural environment. Experimenter still manipulates IV and records DV.
What is a natural experiment?
Researcher uses a naturally occurring IV
E.g. Att. research into the effects of early att. on later relationships.
What is a quasi experiment?
Based on an existing diff. between ps so researcher does not manipulate IV.
What are the strengths of a lab experiment?
- High control = more reliable (replicable) due to standardised procedure
- High validity due to control over extraneous variables
What are the weaknesses of lab experiments?
- Low ecological validity due to artificial setting, likely to increase demand charac.s
- Difficult to genuinely control all extraneous vs, particularly p variables
What are the strengths of field experiments?
- Natural setting = high ecological validity
- Fewer demand charac.s
What are the weaknesses of field experiments?
- Low control over extraneous variables - reduces reliability and validity
- Greater risk of ethical issues (consent)
What are the strengths of natural experiments?
- High ecological validity as the IV is not manipulated and testing ‘real’ issues
- Can investigate issues which are not practical or ethical to manipulate
What are the weaknesses of natural experiments?
- ‘Natural’ events rarely occur
- Experimenter cannot randomly allocate ps to conditions
What are the strengths of quasi experiments?
- More ethical as there is no direct manipulation of IV
What are the weaknesses of quasi experiments?
- Experimenter cannot randomly allocate ps to conditions
- Researcher cannot manipulate IV so cause and effect are difficult to identify
