Correlational Studies

• We use correlation to investigate the relationship between two variables.
• Positive correlation is as one variable increases, the other also increases, the coefficent is 0 to +1, example, the taller the person is the heavier they are
• Negative correlation is as one variable increases, the other decreases where the coeffient is 0 to -1, for example, the more alchol you drink the less you can remeber
• No correlation is where there is no relationship between the variables where the coefficent is close to 0, for exmaple, she sixe and IQ
• Strengths of correlational research:

  • can be used when it would be impracitical or unethical to manipulate variables, such as smoking
  • often high in ecological validity becauseno manipulation of behaviour is required
  • often can be eaisly repeated to find the reliablitity
• Weaknesses of correlational studies:

  • may lack internal/external validity
  • no cause and effect can be inferred