Use
Distribution Overview
Plot to examine reliability data in multiple plots on a single graph. Using the
distribution overview plot, you can do the following:
- Evaluate the fit of the selected
distribution for each variable (or sample)
- Estimate and view the
reliability/survival and hazard functions for each variable (or sample)
independently
- Compare the results for all the
variables (or samples) on each plot
Use this analysis for exact failure times or for any censoring scheme.
- Exact failure data
- Record the failure time at a fixed point in time before the end of the study
or reliability test
- Right-censored data
- Record a time when the unit still survived at the end of the study or
reliability test. For example, a patient may quit a study before it ends, or
a unit is still operating after the allocated testing time. The exact
failure time is unknown but will certainly occur beyond the allocated study
time.
- Interval-censored data
- The exact failure time is unknown, but it occurred in a known interval. For
example, a unit was still operating at 12 when the reliability engineer left
for a mid-day break. Upon the engineer’s return at 12:30 they noticed that
the unit has failed. Thus, the unit failed in the interval starting at 12
and ending at 12:30.
- Left-censored data
- Left-censored data is a special case of interval-censored data point where
the beginning point of the interval may be time 0 or may be unknown. The
engineer only knows that the unit failed by some specific time since the
beginning of the reliability test.
In this analysis, interval censoring allows for the specification of left-censored data
and data that combine different types of censoring. For more information, go to Data censoring.
When you create a distribution overview plot, you choose to display either a parametric overview
plot (by selecting a distribution for your data), or a nonparametric overview plot. The
parametric overview plot includes a probability plot for a selected distribution, a
survival (or reliability) plot, a probability density function, and a hazard plot. For
right-censored data or uncensored data, the nonparametric overview plot includes a
Kaplan-Meier survival plot and a hazard plot or an actuarial survival plot and a hazard
plot. For interval-censored data, the nonparametric overview plot includes a Turnbull
survival plot or an actuarial survival plot and a hazard plot.
Tip
The analysis stores a reliability data definition
that includes the sample columns and the censoring scheme. Select the definition to
quickly run Distribution ID Plot, Distribution Overview Plot, Parametric Distribution Analysis, and Nonparametric Distribution Analysis on the same data.
Where to find this analysis
To create a distribution overview plot, choose .
When to use an alternate analysis
