Scale

Scale (or ratio) data is the highest level of data.

Properties

 * 1) Categories are mutually exclusive
 * 2) Ordinal data allows for rank order (1st, 2nd, 3rd etc.) of data
 * 3) Differences between units is uniform
 * 4) True zero starting point

Examples

 * Temperature (in Kelvin)
 * Age
 * Length