●●● ●●●● ●●●●● ●●●● ●●●●● Definition of conditional probabili ●●●● Definition: Let A and B be two events. The conditional probability that event A occurs, given that event B has occurred, is written P(A B), and is given by P(A B P(A∩B) P(B) Conditional probability provides us with a way to reason about the outcome of an experiment based on partial information o Note: Follow the reasoning above carefully. It is important to understand why he conditional probability is the probability of the intersection within the new sample space Conditioning on event B means changing the sample space to B Think of P(A B)as the chance of getting an A, from the set of B's onlyDefinition of conditional probability Conditional probability provides us with a way to reason about the outcome of an experiment based on partial information