Consider the game of rock-paper-scissors to be an experiment. In the long run, roommate A chooses rock 62% of the time, and roommate B chooses rock 62% of the time; roommate A selects paper 16% of the time, and roommate B selects paper 23% of the time; roommate A chooses scissors 22% of the time, and roommate B chooses scissors 15% of the time. (These choices are made randomly and independently of each other.) The probabilities were assigned using ______.