Experimental methods

• What do experiments allow us to see?

  Cause and effect
• What can researchers manipulate in an experiment?

  Independent variable (IV)
• Why must psychologists choose different experimental methods?

  For different reasons and appropriateness
• What are the three different types of experiments used in research?

  • Laboratory experiment
  • Field experiment
  • Natural experiment
• What is a laboratory experiment characterized by?

  Controlled environment with isolated variables
• What is an example of a laboratory experiment?

  Asch line study
• What is a key advantage of laboratory experiments?

  High levels of control over variables
• What is a field experiment?

  Experiment in a real-life setting
• What does the psychologist manipulate in a field experiment?

  Independent variable (IV)
• What is a limitation of field experiments?

  Can't control extraneous variables
• What is an example of a field experiment?

  Picking up litter in the street
• What characterizes a natural experiment?

  IV occurs naturally in real life
• What does a researcher do in a natural experiment?

  Takes advantage of a pre-existing IV
• What is a quasi-experiment?

  IV naturally occurring, DV measured in lab
• What is the basis of the IV in a quasi-experiment?

  Existing differences between people
• How is the IV treated in a quasi-experiment?

  No one manipulates the variable
• What are the key differences between laboratory, field, and natural experiments?

  • Laboratory: Controlled environment, high control over variables
  • Field: Real-life setting, less control over extraneous variables
  • Natural: IV occurs naturally, no manipulation by researcher