Failure Time Distribution |
Let be a nonnegative random variable that represents the failure time of an individual from a homogeneous superpopulation. The survival distribution function (also known as the survivor function) of
is written as
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A mathematically equivalent way of specifying the distribution of is through its hazard function. The hazard function
specifies the instantaneous failure rate at
. If
is a continuous random variable,
is expressed as
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where is the probability density function of
.