Experimental method

• Field experiment: an experiment conducted not in a lab setting but the IV is still controlled by the researcher. They often have low internal validity but high external validity.
• lab experiments: a study carried out in a highly controlled environment. It has high internal validity due to the controlled variables, but low external validity as it lacks mundane realism.
• natural experiment: the researcher has not directly manipulated the IV, and measures the effect of the IV on the DV.
• quasi experiment: takes place in either a lab or real-life setting and participants are allocated to conditions based on certain characteristics. The IV is the existing conditions/characteristics.
• strength of lab experiments

  High internal validity
• limitation of lab experiments

  Lack of mundane realism
• strength of field experiments

  high ecological validity
• limitation of field experiments

  Less control of extraneous variables
• strength of natural experiments

  Allows research when IV cannot be varied (practicality)
• limitation of natural experiments

  No cause-effect relationship established between variables, as the IV is not manipulated.
• strength of quasi experiments

  Allows for comparisons
• limitation of quasi experiment

  Prone to demand characteristics, low internal validity