Overview of Distribution ID Plot (Right Censoring)

Use Distribution ID Plot (Right Censoring) to determine which distribution best fits your data when you have failure data with exact failures and/or right-censored observations. When data are right-censored, failures are recorded only if they occur before a particular time. A unit surviving longer than that time is considered a right-censored observation. For more information, go to Data censoring.

This analysis allows you to evaluate the fit of 11 parametric distributions that are commonly used to model reliability data: smallest extreme value, Weibull, 3-parameter Weibull, exponential, 2-parameter exponential, normal, lognormal, 3-parameter lognormal, logistic, loglogistic, and 3-parameter loglogistic.

Minitab creates probability plots for the distributions that you select. The probability plots help you determine which, if any, of the parametric distributions best fits your data. In addition, Minitab calculates percentiles and mean time to failure (MTTF) values for each distribution, which provide additional information to consider when selecting a distribution model for reliability analysis. Distribution ID Plot (Right Censoring) can also help you determine whether to use a parametric or nonparametric distribution analysis to further evaluate your data.

Where to find this analysis

To create a distribution ID plot for right-censored data, choose Stat > Reliability/Survival > Distribution Analysis (Right Censoring) > Distribution ID Plot.

When to use an alternate analysis

If your data include either left-censored observations or interval-censored observations, or have a varied censoring scheme that includes exact failure times, right censoring, left censoring, and/or interval censoring, use Distribution ID Plot (Arbitrary Censoring).