M1 - lesson 4

• Levels of Measurement


  The way a set of data is measured
• Levels of Measurement


  • Nominal scale level
  • Ordinal scale level
  • Interval scale level
  • Ratio scale level
• Nominal scale


  Data is qualitative (categorical). Categories, colors, names, labels and favorite foods along with yes or no responses are examples. Nominal scale data are not ordered.

  
• Nominal scale data cannot be used in calculations
• Ordinal scale


  Data can be ordered. An example is a list of the top five national parks in the United States. Responses like "excellent", "good", "satisfactory", and "unsatisfactory" are ordered from most to least desired.
• Ordinal scale data cannot be used in calculations
• Interval scale


  Data has a definite ordering and the differences between data can be measured, but there is no starting point. Examples are temperature scales like Celsius and Fahrenheit.

  
• Interval level data can be used in calculations, but ratios cannot be calculated

  
• Ratio scale


  Data has a 0 point and ratios can be calculated. Examples are exam scores out of 100 points.