Extraneous variables

• What are extraneous variables (EVs)?

  Unwanted variables affecting the DV
• How can extraneous variables (EVs) affect the dependent variable (DV)?

  If they are not controlled
• Where are extraneous variables (EVs) best controlled?

  In a laboratory
• In the "balls in the bucket" experiment, what was the independent variable (IV)?

  Audience or no audience
• In the "balls in the bucket" experiment, what was the dependent variable (DV)?

  Number of balls in the bucket
• Why are standardised instructions important in research?

  To avoid acting as an EV
• What does randomisation involve in research design?

  Using chance to control for bias
• How does randomisation help control for bias?

  By using chance