About Reliability Distribution Analysis Report

The Analysis Summary section of the Reliability Distribution report displays information that is stored in the Reliability Distribution record and Distribution records that are linked to the Reliability Distribution record.

The following table lists each item in the Analysis Summary section and the corresponding Reliability Distribution or Distribution record field whose data is displayed in the report.

The Statistical Distribution Information section of the Reliability Distribution report displays information that is stored in each Distribution record that is linked to the Reliability Distribution record. Each Distribution record is a member of one of four Distribution subfamilies in which records can exist: Exponential, Lognormal, Normal, or Weibull.

The following subsections are displayed for each Distribution record that is linked to the Reliability Distribution:

<Variable> Distribution

In the <Variable> Distribution subsection, <Variable> is the value that is stored in the Variable field in the Distribution record that is linked to the Reliability Distribution record. Throughout the documentation, we will refer to this subsection as the Distribution subsection.

The following table lists each item in the Distribution subsection and the corresponding Distribution record field whose data is displayed in the report.

Report Item	Distribution Field
Distribution Type	Distribution Type
Operating Time Units	Units
Fit Method	Fit Method
R2	R-Squared
Mean	Mean
Standard Deviation	Standard Deviation
Median	Median

Parameters

The Parameters subsection contains information stored in a Distribution record (i.e., Weibull, Lognormal, Exponential, or Normal record). The Weibull, Lognormal, Exponential, or Normal record is linked to the Reliability Distribution record. The items that appear in the Parameters subsection will be different, depending on the type of Distribution record.

The following table lists each item in the Parameters subsection for a Weibull record whose data is displayed in the report. For a Weibull record, one row is displayed for each of the following field captions: Beta, Eta, and Gamma.

Report Item	Weibull Field
Beta
Value	Beta
Low	Beta Low
High	Beta High
Calculated	Beta Fixed
Eta
Value	Eta
Low	Eta Low
High	Eta High
Calculated	Eta Fixed
Gamma
Value	Gamma
Low	Gamma Low
High	Gamma High
Calculated	Gamma Fixed

The following table lists each item in the Parameters subsection for a Lognormal record whose data is displayed in the report. For a Lognormal record, one row is displayed for each of the following field captions: Mu, Sigma, and Gamma.

Report Item	Lognormal Field
Mu
Value	Mu
Low	Mu Low
High	Mu High
Calculated	Mu Fixed
Sigma
Value	Sigma
Low	Sigma Low
High	Sigma High
Calculated	Sigma Fixed
Gamma
Value	Gamma
Low	Gamma Low
High	Gamma High
Calculated	Gamma Fixed

The following table lists each item in the Parameters subsection for an Exponential record whose data is displayed in the report. For an Exponential record, one row is displayed for the field caption MTBF.

Report Item	Exponential Field
MTBF
Value	MTBF
Low	MTBF Low
High	MTBF High
Calculated	MTBF Fixed

The following table lists each item in the Parameters subsection for a Normal record whose data is displayed in the report. For a Normal record, one row is displayed for each of the following field captions: Mean, Standard Deviation.

Report Item	Normal Field
Mean
Value	Mean
Low	Mean Low
High	Mean High
Calculated	Mean Fixed
Standard Deviation
Value	Standard Deviation
Low	Standard Deviation Low
High	Standard Deviation High
Calculated	Standard Deviation Fixed

Goodness of Fit Test

The Goodness of Fit Test subsection displays information from the corresponding Distribution record.

The Kolmogorov-Smirnov test is the only test used to measure goodness of fit, so the Name column in the report is populated automatically with the value Kolmogorov-Smirnov test. The following table lists each remaining item in the Goodness of Fit Test subsection and the corresponding Distribution record field whose data is displayed in the report.

Report Item	Distribution Field
Statistic	GOF Statistic
P-Value	GOF P-Value
Passed	Passed

The Assets section of the Reliability Distribution report displays information that is stored in the Failure Data field in the Reliability Distribution record.

The following values are displayed in the Assets section:

• Asset ID
• Installation Date
• Last Replacement
• Present Age
• Future Age
• Present Failure Probability
• Future Failure Probability

The Functional Failures section of the Reliability Distribution report displays information that is stored in the Failure Data field in the Reliability Distribution record.

The following values are displayed in the Failure Data section:

• Asset ID
• Failure Date
• TTF
• Downtime
• Ignore
• Censored
• Remarks

The Analysis Plots section of the Reliability Distribution report displays the graphs that are displayed in the Time to Failure Distribution section or accessed via the left pane in the Analysis Summary workspace for the selected analysis.

The Plots section displays the following graphs:

• Probability Plot
• Failure Rate Plot
• Probability Density Function Plot
• Cumulative Distribution Function Plot
• Preventative Maintenance Optimization Plot