experiment types

what is a lab experiment

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

pros of lab experiment type

high control over confounding variables and extraneous variables so more certain over cause and effect so high internal validity, more easily replicated

cons of lab experiment type

lack generalisability, artificial not like everyday life, low external validity, rise in demand characteristics pps may change their behaviour, low mundane realism

what is a field experiment

takes place in a natural setting within which the researcher manipulates the IV and records the effect on the DV

pros of field experiment type

high mundane realism, behaviour produced is more valid and authentic, less possibility of demand characteristics, high external validity as participants could be unaware they are being studied

cons of field experiments

loss of control over CVs and EVs, cause and effect may be difficult to establish between the IV and DV, precise replication not possible, ethical issues as participants are unaware they are being studied and may not consent

what is a natural experiment

the change in IV is not brought about by the researcher but would have happened even if the researcher had not been there. the researcher records the effect on a DV they have decided on

pros of natural experiment types

opportunity for research to happen that may be seen as impractical or unethical, high external validity as involves real world issues

cons of natural experiment types

naturally occurring event only happen rarely so less opportunity for research, participants may not be randomly allocated to experimental conditions so researcher is less sure whether IV affected DV, some research may be conducted in a lab and so lacks realism and demand characteristics may be an issue

what is a quasi experiment

a study that has an IV based on existing differences between pps eg gender, no one has manipulated the variable it simply just exists, (strictly speaking it is not an experiment)

pros of quasi experiment type

carried out under controlled conditions so is replicable and high internal validity (shares some strengths of a lab experiment)

cons of quasi experiment type

cannot randomly allocate participants so may be CV, IV is not deliberately changed by researcher therefore we cannot claim that the IV has caused any observable change