Aims, hypotheses + variables

• Aim - Purpose of investigation

  e.g. To investigate whether drinking energy drinks improves people's memory
• Hypothesis - States what you believe to be true

  It is a prediction, a precise and testable statement of the relationship between two variables
• Independent variable - researcher manipulates or alters (change)
• Dependent Variable - Measurement taken by researcher
• Researcher looking how the IV has affected the DV
• Operationalising variables

  Hypothesis must be written in a specific and measurable form

  variables have to be precisely defined and clear
• Extraneous variables - these could affect the results if they are not controlled
• Cofounding variables - are extraneous variables that couldn't be controlled and DID affect the DV
• Alternate hypotheses - state that there is a significant difference between two conditions or relationship between two variables

  Null hypotheses - based on assumption that there is no difference between two conditions or relationship
• Types of Hypotheses:

  Directional (One-tailed) -making specific prediction

  e.g. "Participants who will....compared to participants who"

  Non-directional (two-tailed) - making vague prediction

  e.g. "there will be a difference"