Measurement

The process of applying numbers to objects according to a set of rules.

Four 'scales' of measurement

1. Nominal
2. Ordinal
3. Interval
4. Ratio

Nominal

• "Nominal" stands for "Name" of category
• Numbers are used simply as labels for groups or classes
• It is used for qualitative rather than quantitative data
• Nominal scale is the least powerful level of measurement
• Nominal scales provide convenient ways of keeping track of people, objects, and events.
• One cannot do much with the numbers involved.
• Numbers on the t-shirts of team players
• One cannot usefully average the numbers on the back of a group of players and come up with a meaningful value.
• The counting of members in each group is the only possible arithmetic operation when a nominal scale is employed