Sometimes attributes are raw abstractions from an event or object—for example, a person’s height, the number of words in an email, the temperature in a room, the time or location of an event. But data can also be derived from other pieces of data. Consider the average salary in a company or the variance in the temperature of a room across a period of time. In both of these examples, the resulting data are derived from an original set of data by applying a function to the original raw data (individual salaries or temperature readings).
