Correlation

• Correlation 


  The researcher investigates an association between two variables - doesnt manipulate variables, just studies the relationship
• Co-Variable


  The variables investigates within a correlation (Not DV and IV because its a correlation, not cause and effect)
• Positive correlation


  As one co-variable increases, so does the other
• Negative Correlation

  As one co-variable increases, the other decreases
• Correlation Coefficient

  A number between -1 and +1 that represents the strength and direction of a relationship between two variables
• Scattergraph


  used to show the relationship between variables
• Can not assume causality as we do not know what co-variable causes which to rise
• Strengths of Correlation

  • Precise and quantifiable measure of how two variables are related - suggests ideas for future research
  • Relatively quick and cheap to carry out - no need for controlled environment and no manipulation of variables, also uses secondary data
• Weaknesses of Correlation

  • Cannot tell us what variables are related as there no manipulation
  • Possible third variable may be causing the correlation (third variable problem)