Accelerated Life Testing - Estimate
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Stat > Reliability/Survival > Accelerated Life Testing > Estimate

Allows you to estimate percentiles and survival probabilities for predictor values, percentiles for given percents and survival probabilities for times.

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Percentile and Probability Estimation

Enter new predictor values: Enter new values or columns of new values. The number of new predictor values  must equal the number of predictors in the model; the first value or column corresponds to the first variable, the second value or column corresponds to the second variable, and so on. For example, it is common to enter the design value, or common running condition, for the units.

Use predictor values in data (storage only): Choose to use the predictor values from the data to estimate percentiles and/or survival probabilities.

Estimate percentiles for percents: Enter the percents for which you want to estimate percentiles. By default, Minitab estimates the 50th percentile. If you want to look at the beginning, middle, and end of the product's lifetime for a given predictor value, enter 10 50 90 (the 10th, 50th, 90th percentiles). Minitab then estimates how long it takes for 10% of the units to fail, 50% of the units to fail, and 90% of the units to fail.

Store percentiles

Percentiles: Check to store the percentiles.

Standard error: Check to store the standard error of the percentiles.

Confidence limits: Check to store the confidence limits for the percentiles.

Estimate probabilities for times: Enter the times for which you want to estimate survival probabilities or cumulative failure probabilities.

Estimate survival probabilities: Choose to estimate the survival probabilities.

Estimate cumulative failure probabilities: Choose to estimate the cumulative failure probabilities.

Store probabilities

Probabilities: Check to store the survival probabilities or cumulative failure probabilities.

Confidence limits: Check to store the confidence limits for the survival probabilities or cumulative failure probabilities.

Confidence level: Enter the confidence level for all of the confidence intervals. The default is 95%.

Confidence intervals: Choose to use two-sided confidence intervals (the default) or just an upper or lower confidence bound.