# Analysis of Variance

## Analysis of Variance

The ANOVA table has 4 forms:

Source DF F_inc
Source DF F_inc F_con M
Source DF DDF_add F_inc P_add
Source DF DDF_con F_inc F_con M P_con

depending on whether conditional F-statistics are reported (requested
by the
!FCON qualifier
) and whether the denominator degrees
of freedom are reported.
ASReml always reports incremental F-statistics ( F_inc) for the fixed model terms
(in the DENSE partition) conditional in the order the terms were
nominated in the model.
Users should consult the Theory chapter of the
User Guide
for details of this table.
The 'conditional maximum' model used as the basis for the conditional F-statistic
is spelt out in the .aov file.
The numerator degrees of freedom for each term is easily determined
as the number of non-singular equations involved in the term.
However, in general, calculation of the denominator degrees of freedom
is not trivial. ASReml will by default attempt the calculation
for small analyses, by one of two methods. In larger analyses,
users can request the calculation be attempted using the
!DDF qualifier.
Use !DDF -1 to prevent the calculation.
## See Also

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