The average probability, P(E), for all branches leaving an event node is 1/n, where n is the number of branches leaving that event node.

Question

Quizplus · Accepted Answer

This is known as the principle of equally likely outcomes, which states that if all outcomes of an event are equally likely, then the probability of any one outcome is the quotient of the number of favorable outcomes divided by the total number of possible outcomes. In this case, if there are n equally likely branches leaving an event node, then each branch has a probability of 1/n. Therefore, the average probability for all branches leaving that event node is also 1/n.

The Average Probability, P(E), for All Branches Leaving an Event