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• What are variables in an investigation?

  Anything that can vary or change within an investigation
• What are the vital components of any experiment?

  The independent and dependent variables
• How can you identify if a study is following an experimental methodology?

  By the presence of independent and dependent variables
• What happens if there is no independent or dependent variable in a study?

  The study is considered non-experimental
• What is the independent variable (IV)?

  The variable manipulated by the researcher
• What is the dependent variable (DV)?

  The variable measured by the researcher
• Why should all other variables remain constant in an experiment?

  To ensure any change in the DV is due to the IV alone
• What are different experimental conditions needed for?

  To test the effect of the independent variable
• What is an extraneous variable (EV)?

  Any variable other than the IV that may affect the DV
• What happens if extraneous variables are not controlled?

  They become confounding variables
• What is the difference between participant variables and situational variables?

  Participant variables are individual differences, while situational variables are features of the experimental situation
• What are confounding variables?

  Variables that vary systematically with the IV and decrease validity
• What is the operationalization of variables?

  Making variables as measurable as possible
• What is a directional hypothesis?

  A hypothesis that specifies the expected direction of the effect
• Give an example of a directional hypothesis.

  After drinking 300 ml of speedup, participants say more words than those who drink 300 ml of water
• What is a non-directional hypothesis?

  A hypothesis that states there will be a difference without specifying the direction
• Give an example of a non-directional hypothesis.

  There will be a difference in the number of words spoken between participants who drink speedup and those who drink water