Probability theory

Combinatorics in probability

Outcome counts, sampling and hypergeometric models.

Probability theory

Permutations of n elements

Pₙ = n!→
Probability theory

Permutations with repetition

P = n!/(n₁!n₂!…)→
Probability theory

Number of unordered samples

Cₙᵏ→
Probability theory

Number of ordered samples

Aₙᵏ→
Probability theory

Independent trials outcome count

N = mⁿ→
Probability theory

Hypergeometric probability

P(X=k)=C(K,k)C(N−K,n−k)/C(N,n)→
Probability theory

Probability all birthdays are distinct

P = 365·364·…/(365ⁿ)→