Types of experiments Flashcards
what is a lab experiment?
an experiment that takes place in a controlled environment within which the researcher manipulates the IV and records the effect on the DV. whilst maintaining strict control of extraneous variables.
strengths of a lab experiment
•they have a high control over extraneous variables meaning that the researcher can ensure that the outcome of the DV is due to the manipulation of the IV
•high internal validity
•can be easily replicated so the validity of the study can be proved/ disproved
limitations of a lab experiment
•they may lack generalisability as the tasks/ environment are artificial meaning the findings may not be applicable to everyday life
•low external validity
•participants are usually aware they are being tested which may lead to demand characteristics and the participant giving the ‘social desirable’ answer- loses validity
•tasks do not represent real life, so it has low mundane realism
what is a field experiment?
an experiment that takes place in a natural setting within which the researcher manipulated the IV and records the effect on the DV
strengths of a field experiment
•they have a higher mundane realism than lab experiments due to the natural environment
•high external validity, as participants may not be aware they are being studied- no demand characteristics
limitations of a field experiment
•lack of control over extraneous variables means that it cannot be certain what effected the DV and replication is often not possible (environmental/ situational variables)
•ethical issues may arise if the participants are unaware they are being studied, like lack of consent and an invasion of privacy
what is a natural experiment?
an experiment where the change in the IV is not brought about by the research but would have happened even if the researcher had not been there. the researcher records the effect of the DV.
strengths of a natural experiment
•provides opportunities for research that may not have otherwise occurred due to practical/ ethical reasons
•high external validity as they study real- life situations
limitations of natural experiments
•a naturally occurring event may only happen very rarely, reducing the opportunities for research, this may affect the generalisability
•participants may not be randomly allocated to experimental conditions, this means that the researcher may be less sure whether the IV affected the DV. there might also be confounding variables affecting their behaviour
what is a quasi- experiment?
an experiment where the effect of the pre- existing differences between people are examined (for example, the effects of gender or age on behaviour)
a strength of quasi experiments
•often carried out under controlled conditions and therefore share the strengths of a lab experiment
limitation of a quasi experiment
•these experiments, like natural experiments, cannot randomly allocate. participants to conditions and therefore there may be confounding variables
