Consider how we might create a definition for the expectation of a given outcome. To do so, first consider a desired collection of outcomes A. If each outcome in A is chosen randomly then we might consider using a formula similar to relative frequency and set a measure of expectation to be |A|/|S|. For example, on a standard 6-sided die, the expectation of the outcome A={2} from the collection S = {1,2,3,4,5,6} could be |A|/|S| = 1/6.