Starting estimates and historical estimates
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You must enter starting estimates or historical estimates for each distribution of failures each parameter you wish to estimate. Each variable, By variable group level, and failure mode represents a unique distribution that requires estimates in one single column or in separate columns. See the following table for various scenarios:

Variables with single failure modes:

Case

Enter

A single variable with a single failure mode.

·    Enter one column containing values for each parameter of your distribution.

Two or more variables, each with a single failure mode.

·    Enter a single column containing values for each parameter for each variable.

·    Enter one column of parameter estimates for each variable.

A By variable with several group levels.

·    Enter a single column containing values for each parameter for all group levels.

·    Enter one column of values for each group level. If there are four group levels, enter four columns containing parameter estimates.

Variables with multiple failure modes:

Case

Enter

A single variable with a multiple failure modes.

·    Enter a single column containing values for each parameter for each failure mode.

·    Enter one column of parameter estimates for each failure mode. If there are three failure modes, enter three columns of parameter estimates.

Two or more variables, each with multiple failure modes.

·    Enter a single column containing values for each parameter for each failure mode and variable.

·    Enter one column of parameter estimates for each failure mode of each variable. If there are two variables with two failure modes, enter four columns of parameter estimates.

A By variable with several group levels and multiple failure modes.

·    Enter a single column containing values for each parameter for each failure mode of each group level.

·    Enter one column of parameter estimates for each failure mode of each group level. If there are two group levels with three failure modes each, enter six columns of parameter estimates.

Parameter estimates are assigned by failure mode then variable. Normally, the first column should contain the parameter estimates of failure mode 1, variable 1; the second column - parameter estimates of failure mode 1, variable 2, etc. If variable 2 does not have failure mode 1, the second column contains the parameter estimates of failure mode 2, variable 1.

Caution

Do not enter starting estimates or historical estimates for failure modes that you have eliminated from the analysis.