Specify methods to estimate the distribution parameters for Nonnormal Capability Analysis for Multiple Variables

Stat > Quality Tools > Capability Analysis > Multiple Variables (Nonnormal) > Estimate

You can have Minitab estimate the parameters of the nonnormal distribution that you use for the capability analysis, or you can enter some or all of the parameters below. Enter the parameter values directly as constants or enter columns that contain the values. The number of constants or values in the column must equal the number of parameters.

  • Estimate parameters of distribution: Estimate the distribution parameters from the sample data. Minitab estimates any parameters that you do not specify below.
    Set shape (Weibull or gamma) or scale (other dists) at
    Enter the shape or scale parameters, depending on the type of distribution you selected. The shape parameter affects the shape of the distribution, such as its skewness.
    Set threshold at
    If you selected a 3-parameter distribution, enter the threshold parameter. The threshold parameter sets the minimum location of the data distribution.

    For more information on the shape, scale, or threshold of a distribution, go to Process data for Nonnormal Capability Analysis for Multiple Variables and click the parameter that you want to learn more about.

  • Use historical estimates: Specify historical estimates of the parameters. Enter constants or a column using the parameter order shown. If all variables share the same parameter values, you can enter constants or a single column. If each variable has different parameter values, enter a separate column for each variable.