Probability Formulas Flashcards
1
Q
What is P(A)
A
probability an outcome will belong to event A
2
Q
What is A^c
A
Complement. all outcomes not included in event A
3
Q
Complement formula
A
P(A)^c = 1 - P(A)
4
Q
Or formula
A
P(A u B) = P(A) + P(B) - P(A n B)
5
Q
And formula
A
P(A n B) = P(A) x P(B|A) OR P(B) x P(A|B)
6
Q
What is conditional probability?
A
The probability of belonging to B given we know it belongs to A. Denoted as (B|A). For example what is the probability of a card being a face card knowing that it is Red -> P(F|R)
7
Q
What is Disjoint
A
When A and B are mutually exclusive, Ie no one said yes to both. P(A n B) when disjoint is 0
8
Q
Independence
A
When A and B are independent, P(A n B) = P(A) * P(B)
9
Q
Conditional probability formula
A
P(A|B) = P(A n B) / P(B)
