Poisson Distribution Calculator
Poisson probabilities for a given rate λ: exactly k events, at most k and at least k, with the probability chart.
Poisson probabilities for a given rate λ: exactly k events, at most k and at least k, with the probability chart.
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The Poisson distribution models the number of events in a fixed interval when events occur independently at a constant average rate λ — calls per hour, defects per metre, arrivals per minute.
Example
λ = 3, k = 2
→ P(X = 2) ≈ 0.2240418077
Probability mass function.
The mean and the variance are both λ.