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The MAIN EFFECTS and INTERACTIONS of the grouping variables to be
included in the model are given by the INCLUDED parameter. The
grouping variables are referenced by their initials, which should
be unique. Only hierarchic models may be formed by ANOVA operation,
i.e. if an interaction term is included in the model then all
lower order interactions included in it are added in the model, too.
For example the two definitions
   INCLUDED=A,B,AB      INCLUDED=AB
yield the same model. Sometimes, it is easier to specify those
interactions excluded from the model by the parameter EXCLUDED. If
an interaction is excluded from the model then it follows that
all higher order interactions, which include that interaction, are
excluded also, e.g. in a three-way model the definitions
   EXCLUDED=AB          EXCLUDED=AB,ABC
yield the same model. If both the parameters are used in the same
time then interactions are first included and second excluded. The
default model is always model with all possible interactions.

Further information:
   1 = More on definitions for grouping variables 
   V = More on analysis of variance for multiple factors 
   C = More on analysis of covariance 
   A = More on ANOVA operations