Elements of an experiment

• AIM:

  What the researcher intends to investigate
• Hypothesis

  • Prediction of outcome
  • Non-directional / Directional & a Null written
• DIRECTIONAL HYPOTHESIS:

  • (one-tailed) Indicates a direction in the prediction
• Non-directional hypothesis:

  • Two-tailed
  • Doesn’t indicate a direction in prediction
• Null:

  • No RESULT
  • No RELATIONSHIP between the 2 variables being studied
• Independent variable:

  • Is manipulated
  • Direct effect on the DV
• DEPENDENT VARIABLE:

  • Is measured as the IV is manipulated
  • Data collected
• Extraneous Variables:

  • Not IVs 
  • May affect the results of the experiment
  • Two types, Situational, Participant
• SITUATIONAL:

  • Aspects of the environment which may affect the participant’s behaviour
  • e.g. noise , weather , instructions , time of day
• Participant:

  • How each person varies from the other
  • e.g. mood, intelligence, age, gender 
• CONFOUNDING VARIABLES:

  • Extraneous variables not controlled- become confounding variables
  • Create same results of the IV, can no longer conclude a causal relationship