Variables

• What is the independent variable (IV)?

  The variable that changes or is manipulated (by the researcher) to see if it has an effect on the DV.
• What is the dependent variable (DV)?

  The variable that the researcher measures. To see the effect of the IV.
• What are extraneous variables (EV)?

  Unwanted extra variables other than the IV that could have an effect on the DV - lowering the internal validity of the study.
• What are the causes of extraneous variables?

  1.Situational factors - environment e.g. task difficulty or standardised instructions.

  2. Participant variables - participants e.g. ages, gender, IQ, eyesight, hearing, personality etc.

  3. Experimenter variables - researcher e.g. investigator effects.
• What type of design do participant variables ONLY effect?

  Independent groups design.
• What are confounding variables?

  When an extraneous variable is not controlled and impacts the outcome of the study.
• What is the difference between extraneous variables and confounding variables?

  Extraneous - may have an effect on the DV.

  Confounding - has an effect on the DV