Table of survival probabilities for Accelerated Life Testing

The table of survival probabilities indicates the probability that the product survives until a particular time at specified levels of the accelerating variable. Use these values to determine whether your product meets reliability requirements, or to compare the reliability of two or more product designs.

The table of survival probabilities consists of the following columns:

Time, which is the particular time until a certain probability of the product is predicted to survive.
Temp, which is the temperature for which estimates are provided.
Probability, which is the chance that the product will survive until a particular time.
95% confidence interval, which provides a range of values that is likely to contain the true value of the parameter.

Use these values only with an appropriate model for the data. If the model fits the data poorly, then these estimates may not be accurate.

Example output

Table of Survival Probabilities

			95.0% Normal CI
Time	Temp	Probability	Lower	Upper
730	55	0.951911	0.586404	0.995460
730	85	0.632592	0.069043	0.924548

Interpretation

For the electronic device data, the estimated two year (730 days) reliabilities are provided:

At the design temperature of 55°C, 0.951911, or 95.1911%, of the electronic devices will survive at least two years..
At the worst-case temperature of 85°C, 0.632592, or 63.2592%, of the electronic devices will survive at least two years.