Research issues

• What is the key to an experiment?

  Manipulating the independent variable (IV)
• What should only influence the dependent variable (DV)?

  The independent variable (IV)
• What are extraneous variables?

  Unwanted variables that interfere with IV or DV
• How are extraneous variables managed in a study?

  Identified and minimized by the researcher
• What are nuisance variables?

  Extraneous variables that do not vary systematically
• How do nuisance variables affect experimental results?

  They make it harder to detect a result
• What are confounding variables?

  Variables that change systematically with the IV
• In the energy drink study, what unintended IV was introduced?

  Excitement of the first ten participants
• Why is it difficult to determine the cause of changes in the DV?

  Because excitement varied systematically with IV
• What are demand characteristics?

  Clues that help participants guess the study's aims
• How do participants react to demand characteristics?

  They may alter their behavior to fit expectations
• What is the 'please-U effect'?

  Participants overperform to please the experimenter
• What is the 'screw-U effect'?

  Participants underperform to sabotage the study
• What are investigator effects?

  Unwanted influences of the investigator on outcomes
• How can investigator effects manifest in a study?

  Through unconscious cues or expectancy effects
• What is randomisation in research?

  Using chance methods to reduce biases
• How should the order of conditions be determined in an experiment?

  It should be randomly determined for each participant
• What is the purpose of standardisation in research?

  To ensure all participants have the same experience
• What are the steps to minimize extraneous/confounding variables?

  • Identify extraneous variables
  • Control or remove them
  • Use randomisation
  • Standardize procedures
• What are the differences between extraneous, confounding, and nuisance variables?

  • Extraneous variables: Unwanted variables affecting IV or DV
  • Confounding variables: Change systematically with IV
  • Nuisance variables: Do not vary systematically with IV