correlations

• what is a correlation?

  a mathematical technique that researchers use to investigate an association (relationship) between two or more variables which are co-variables
• what type of graph is used for correlations?

  scatter graph
• what are the types of correlation?

  • positive correlation
  • negative correlation
  • zero correlation
• what is a positive correlation?

  A positive correlation is a relationship between two variables where they both increase or decrease together.
• what is a negative correlation?

  Inverse relationship between two variables. Where one variable increases another variable decreases.
• what is a zero correlation?

  No relationship between the co-variables
• how do you know if the correlation is positive or negative?

  • if the value is over 0: (1) then the correlation is positive
  • if the value is under 0: (-1) then the correlation is negative
  • the relationship of the variables will produce a co-efficient between 1 and -1
• a correlational hypothesis:


  the hypothesis will state the relationship between the variables and must be operationalised
• strength of correlations


  • quick/less time consuming and economical
  • no need for a controlled environment
  • secondary data collected (by others) can also be used
• limitation of correlations


  • correlations cannot establish cause and effect/direction of effect, because they only tell us how the variables are related and not why. Therefore we don't know which co-variable is causing the other to change