Correlations

• What is a correlation?

  A relationship between two co-variables
• What is a correlation coefficient?

  A number between -1 and +1 that measures the strength of a correlation.

  Closer to +1 = stronger positive correlation

  Closer to -1 = stronger negative correlation
• What is the difference between a correlation and an experiment?

  Correlations are non-experimental: there’s no IV or DV manipulation

  Therefore we can’t measure cause and effect
• What are the strengths of correlations?

  • Used for preliminary work, as it shows a link between two variables and means further research can occur
  • Data can be secondary (collected by others), making the research quick
• What are the weaknesses of correlations?

  • Do not show cause and effect
  • Direction of effect: which variable influences the other?
  • May be a third variable causing the affect