Probability theory

Poisson distribution

Rare-event probabilities, rates, mean and standard deviation.

Probability theory

Poisson probability of k events

P(X=k)=e⁻λλᵏ/k!→
Probability theory

Poisson probability of zero events

P(X=0)=e⁻λ→
Probability theory

Poisson: at least one event

P(X≥1)=1−e⁻λ→
Probability theory

Poisson: up to k events

P(X≤k)=Σe⁻λλⁱ/i!→
Probability theory

Poisson parameter from rate

λ=rt→
Probability theory

Poisson mean

μ=λ→
Probability theory

Poisson standard deviation

σ=√λ→