In the 1920s, E. J. Gumbel was the first to seriously investigate extreme values in failure data, finding that there are only six separate extreme value distributions. His Type III smallest extreme value distribution is the same as the Weibull distribution. For more information, see Weibull Distribution.

Gumbel distributions are recommended when failure is a result of rare events and failure values are extreme. Examples include natural disasters and maximum guest loads. Only the Weibull module makes the Gumbel distributions available. In this module, you can uses these distributions to analyze life data sets.

Because Gumbel distributions (and normal distributions) can predict negative life for high reliability requirements, an impossibility with life data, care must be taken when using them to model life data. For more information, see: