Specify the estimation options for Warranty Prediction

• Calculate optimal estimates: Select to have Minitab estimate the failure time distribution based on your sample data.
• Enter user-defined estimates: Select to enter the parameters of the distribution based on historical knowledge or the results of a parametric distribution analysis. Then enter a column that contains the parameter values that you want to use for the analysis. The column must contain the same number of parameters as the distribution that you select for the analysis.

• Maximum Likelihood: Estimate the distribution parameters by maximizing the likelihood function.
• Least Squares (failure time(X) on rank(Y)): Estimate the distribution parameters by fitting a regression line to the points on a probability plot.

For more information on these two methods, go to Least squares estimation method and maximum likelihood estimation method.