Hi~
When I study fit model, I have a simple problem. As you see below image, I want to know why "Lack of Fit" is not activated, this sample data just from JMP library.

Thanks a lot, I have to study more with Books that you recommanded~
The documentation for the Fit Model Platform has the following statement:
In the following situations, the Lack of Fit report does not appear because the test statistic
cannot be computed:
• There are no replicated points with respect to the X variables, so it is impossible to
calculate a pure error sum of squares.
• The model is saturated, meaning that there are as many estimated parameters as
there are observations. Such a model fits perfectly, so it is impossible to assess lack of fit.
The documentation is available from the pull down menus in JMP:
Help==>Books==>Fitting Linear Models