Weibull distribution

Definition taught in Reliability, part of Probability

Weibull distribution

Weibull hazard rates with rate \lambda=1. From Reliability.
Type Definition
Taught in Reliability
Part Probability

A lifetime T is Weibull with shape \beta>0 and rate \lambda>0 when its density is \lambda\beta\,(\lambda t)^{\beta-1}\exp(-(\lambda t)^\beta) for t>0. The survival function is \exp(-(\lambda t)^\beta), the distribution function is 1 minus that survival function, and

\mathbb{E} T=\frac{\Gamma(1+1/\beta)}{\lambda}.

The shape \beta=1 is the exponential distribution with rate \lambda.

Used in

See also

Survival function · Cumulative distribution function · Exponential distribution · Structure function · Reliability function · Hazard rate

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