A probability space is a setS, together with a σ-algebraX on S and a measureP on that σ-algebra such that P(S) = 1.
The set S is called the sample space and the elements of X are called the events.
The measure P is called the probability measure, and P(E) is the probability of the event E.
... housing units at an average density of 789.1/km² (2,045.6/mi²). The racial makeup of the town is 88.27% White, 3.90% African American, 0.20% Native American, ...