correlation

• Correlation


  A mathematical technique that is used to investigate an association between two variables which are called co-variables
• Correlations differ to experiments as the variables are simply measured, not manipulated like in experiments, and only an association is found, no cause-and-effect relationship found hence the terms DV and IV are not used
• Negative correlation


  When one variable increases the other decreases
• Positive correlation


  When one variable increases the other also increases
• Zero correlation


  No relationship is found between the co-variables
• Curvilinear relationship


  As one variable increases, so does the other but only up to a certain point after which as one variable continues to increase the other begins to decrease
• Strengths of correlations

  • They can be used as starting points to assess patterns between co-variables before committing to conducting an experimental study
  • Quick and economical to carry out
  • Secondary data can be used in the correlational study which makes it even less time consuming
• Limitations of correlations

  • It is difficult to establish a cause and effect relationship, really only an association is found
  • The third variable problem is presented - this is when there is a chance that there is another variable, a third variable which the researcher is unaware of that is responsible for the relationship between the co-variables
  • Correlations tend to be misused or misinterpreted especially when made public by the media - correlation is often presented as causation