Exponential Distribution
X ~ Exp(λ)
Memoryless / Waiting-Time Family • Published July 18, 2026
The waiting-time distribution: history from Erlang's queueing theory and radioactive decay, the memoryless property, rate-vs-scale parameterization, the full property list (including its defining constant hazard function), maximum-likelihood estimation of the rate with its small-sample bias, and exact simulation via inverse-transform sampling.
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About This Reference Sheet
The waiting-time distribution: history from Erlang's queueing theory and radioactive decay, the memoryless property, rate-vs-scale parameterization, the full property list (including its defining constant hazard function), maximum-likelihood estimation of the rate with its small-sample bias, and exact simulation via inverse-transform sampling.
Support
x ∈ [0, ∞)
Parameters
λ > 0 (rate)