Weibull Parameters Pane for a Reliability Growth Data Set

Windchill Risk and Reliability Desktop Help > Windchill Weibull > LDA (Life Data Analysis) > Reliability Growth Analysis > Weibull Parameters Pane for a Reliability Growth Data Set

When a reliability growth data set is selected in the LDA Navigator, you supply the basic parameters needed for this type of analysis in the Weibull Parameters pane. The following table describes all of the parameters that can appear in this pane when Reliability Growth is the analysis type.

Parameter	Description
Data type	The type of model to use for the data in the reliability growth data set. Choices are Duane Cumulative, Duane Interval, Crow/AMSAA Cumulative, and Crow/AMSAA Interval. The default is Duane Cumulative. The selection you make here affects the estimation method selected in the Weibull Advanced pane. For more information, see Weibull Advanced Pane for a Reliability Growth Data Set. It also affects the columns available in the Weibull Data Points pane. For more information, see Weibull Data Points Pane for a Reliability Growth Data Set.
Calculation results The display-only results under this heading show the parameter values for the selected estimation method once the data set has been calculated. • When a Duane data type is selected, the ranked regression estimation method is used. In this case, λ, β, α, and ρ2 are calculated. • When a Crow/AMSAA data type is selected, the MLE estimation method is used. Because MLE does not result in X and Y values that can be plotted on a probability plot, no ρ2 value is associated with it. In this case, only λ, β, and α are calculated.

Parameter

Description

Data type

The type of model to use for the data in the reliability growth data set. Choices are Duane Cumulative, Duane Interval, Crow/AMSAA Cumulative, and Crow/AMSAA Interval. The default is Duane Cumulative. The selection you make here affects the estimation method selected in the Weibull Advanced pane. For more information, see Weibull Advanced Pane for a Reliability Growth Data Set. It also affects the columns available in the Weibull Data Points pane. For more information, see Weibull Data Points Pane for a Reliability Growth Data Set.

Calculation results

The display-only results under this heading show the parameter values for the selected estimation method once the data set has been calculated.

• When a Duane data type is selected, the ranked regression estimation method is used. In this case, λ, β, α, and ρ2 are calculated.

• When a Crow/AMSAA data type is selected, the MLE estimation method is used. Because MLE does not result in X and Y values that can be plotted on a probability plot, no ρ2 value is associated with it. In this case, only λ, β, and α are calculated.