Conditioning on event B restricts the sample space to only the outcomes contained within B. Within this newly restricted space, the favorable outcomes for event A are located exclusively in the intersection of A and B (A∩B).
Conditions: Event B has occurred.; We are calculating the conditional probability of A given B.
Conditioning on event B restricts the sample space to only the outcomes contained within B. Within this newly restricted space, the favorable outcomes for event A are located exclusively in the intersection of A and B (A∩B).
Conditions: Event B has occurred.; We are calculating the conditional probability of A given B.
For a conditioning event with positive probability, the formula is P(A∣B)=P(A∩B)/P(B). On a Venn diagram, the overlap region (A∩B) serves as the numerator, and the entire conditioning region (B) serves as the denominator.
Conditions: The conditioning event B has a positive probability (P(B)>0).
For a conditioning event with positive probability, the formula is P(A∣B)=P(A∩B)/P(B). On a Venn diagram, the overlap region (A∩B) serves as the numerator, and the entire conditioning region (B) serves as the denominator.
Conditions: The conditioning event B has a positive probability (P(B)>0).
Swapping the events changes both the numerator and the denominator in the conditional probability formula. P(A∣B) uses P(A∩B) as the numerator and P(B) as the denominator, whereas P(B∣A) uses P(A∩B) as the numerator but P(A) as the denominator.
Conditions: Events A and B have different marginal probabilities (P(A)=P(B)).; Both events have positive probability.
Swapping the events changes both the numerator and the denominator in the conditional probability formula. P(A∣B) uses P(A∩B) as the numerator and P(B) as the denominator, whereas P(B∣A) uses P(A∩B) as the numerator but P(A) as the denominator.
Conditions: Events A and B have different marginal probabilities (P(A)=P(B)).; Both events have positive probability.