What are the types of extraneous variables?

There are 4 main types of extraneous variables:

  • Demand characteristics: Environmental cues that encourage participants to conform to researchers’ expectations
  • Experimenter effects: Unintentional actions by researchers that influence study outcomes
  • Situational variables: Eenvironmental variables that alter participants’ behaviours
  • Participant variables: Any characteristic or aspect of a participant’s background that could affect study results