LEVELS OF MEASUREMENT

• What is nominal data?

  Means name and gives each participant a name or label

  e.g good or bad.
• What is ordinal data?


  Means order, ranks data from first to last and classifies variables into categories.

  E.g. we can rank participants form highest to lowest score.
• What is an example of nominal data?


  Eye colour; blue, brown and green.
• What is interval data?


  Measures an attribute on a standardised scale, and is numerical. It has equal intervals between adjacent names.
• What is an example of interval data?


  Length, time and mass.

  cm, secs, grams.
• Interval data is the most precise, then ordinal and nominal.

  Interval data gives the most information.

  Interval data can also be converted into ordinal data, but ordinal data cannot be converted into interval data.
• Example: psychology test results

  Nominal - pass or fail.

  Ordinal - your position/rank in the class.

  Interval - your mark as a percentage.