A preference relation of player over a set of outcomes is a binary relation denoted by .
as "player either prefers to or is indifferent between the two outcomes"
The preference relation over is complete, that is, for any pair of outcomes and in , either , or , or both.
The preference relation over is reflexive, that is, for every .
The preference relation over is reflexive, that is, for any triplet of outcomes , , and in , if and then .