Occasional job qualifiers.

Context: Defining the F test

!FOWN qualifier

allows the user to specify the test in the 'conditional' F-statistic column to the table of Wald F statistics. It has the form !FOWN terms_t_tst ; background_trms placed on a separate line immediately before or after the model line. Multiple !FOWN statements should appear together. It generates an F-test statistic for each model term in terms_t_tst which tests its contribution after all after terms in terms_t_tst and background_trms, conditional on all terms that appear in the SPARSE equations, and on not changing the degrees of freedom associated with a term. It should only include terms which will appear in the ANOVA table. For example,

 !FOWN  A B C ; mu
 !FOWN  A.B B.C A.C ; mu A B C
 !FOWN  A.B.C  ; mu A B C A.B B.C A.C

would request the tests

  F( A ; mu B C  sparse),
  F( B ; mu A C  sparse),
  F( C ; mu A B  sparse),
  F( A.B ; mu A B C B.C A.C sparse),
  F( B.C ; mu A B C A.B A.C sparse),
  F( A.C ; mu A B C A.B B.C sparse)
  F( A.B.C ; mu A B C A.B A.C B.C  sparse).

Warnings:

This qualifier is provided for advanced users who have a good understanding of marginality issues in ASReml. ASReml does not verify the tests requested satisfy marginality considerations which are normally relevant. Any model terms in the !FOWN lists which do not appear in the actual model, are ignored without flagging an error. Any model terms which are omitted from !FOWN statements are tested with the usual conditional test. If any model terms are listed twice, only the first test is performed. F-con tests specified in !FOWN statements are given model codes O, P, ....

The !FOWN statements are parsed by the same routine that parses the model line and so accepts the same model syntax options. Care should be taken to ensure term names are consistently spelt. If the !FOWN statements appear before the model line, model terms that are not previously defined may not be abbreviated (truncated) in !FOWN statements relative to their form in the model line because they are defined on their first appearance.

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