Levels of measurements

• Nominal data -

  > Data in the form of categories

  > For example: you can count how many boys and girls are in your year group – male and female are the categories and you can count how many are in each group
• Ordinal data -

  > Ordinal data is ordered/ranked in some way

  > Does not have equal or fixed intervals between each unit

  > Data is based on subjective opinions

  > Another example of ordinal data would be the amount of items recalled in a a memory test or score on an IQ test

  > Ordinal data is often known as ‘unsafe’ data due to its lack of precision
• Interval data -

  > Data is a standardised / universal measurement

  > Data is based on objective measures eg. time in seconds or centimetres

  > Interval is based on numerical scales