Levels of measurement

• How many levels of measurement are there?

  Four
• What is nominal data?

  • Categorizes data into groups
  • Counts how many fall into each category
  • Example: Number of people liking different foods
• What is ordinal data?

  • Orders data into ranks
  • Example: Ranking favorite TV shows
  • Indicates preference order
• What is interval data?

  • Measured along a numerical scale
  • Equal distances between adjacent values
  • No true zero point
  • Example: Temperature
• What distinguishes interval data from ratio data?

  No true zero point
• What is ratio data?

  • Quantitative data with interval properties
  • Equal and definitive ratio between values
  • Absolute zero as a point of origin
  • Example: Height and weight
• What does absolute zero mean in ratio data?

  It is the point of origin
• How do the properties of ratio data compare to interval data?

  Ratio data has a true zero, interval does not