Waiting-time distribution
= Waiting-time distribution
{title2=$p(t)=-S'(t)$}
The <probability distribution> of a nonnegative duration until an event. For a continuous duration with <survival function> $S(t)=P(T>t)$, its <probability density function> is $p(t)=-S'(t)$. A constant hazard gives an <exponential distribution>; successive independent first-order waits give a convolution, as in the <two-step catalytic waiting time>.