exponential distribution

exponential distribution
a skewed probability distribution with right tail extending to infinity and having the density function

f(x) = λe−λx

for x ≥ 0 and λ > 0. The mean is 1/λ and the variance is (1/λ)2. The mode is at zero and the larger the parameter λ, the more clustered the distribution toward zero. The exponential distribution arises in medicine and reliability as the time to mortality/morbidity or failure; λ is often interpreted as the force of mortality or failure.


Medical dictionary. 2011.

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