The lifetime of a device has a Gompertz distribution. Find the reliability of the device:
The hazard function increasing in time:
Find the reliability of two such devices in series:
Find the reliability of two such devices in parallel:
Compare the reliability of both systems for

and

:
A steel pipe with thickness

is exposed to corrosion and fails if any of the
n microscopic pits penetrates the surface. Assume the time to penetration at each pit is proportional to the remaining thickness with factor
k. If the depths of the pits are initially random and each follows a right-truncated exponential distribution with parameter

, then time to failure of the pipe follows a Gompertz distribution. Find the reliability of the pipe:
Find the mean time to failure:
The female mortality in 1900 according to the Society of Actuaries is given by the table:
Create a sample population to use maximum likelihood estimation:
Fit a Gompertz-Makeham distribution into the data:
Plot probability density function:
Compare the mortality data with the survival function of the estimated distribution:
Find the average female life length in 1900:
Compare the mean residual lifetime from the data with estimated distribution:
Define expo-power distribution using Gompertz distribution:
Hazard function:
Survival function:
Probability density function:
WeibullDistribution is a limiting case: