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ASReml-S reference manual - VSN International

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6.2 The predict method 63sedvcova list of length the number of classified tables, and named by the classify set.Each component is a logical scalar (default F) that determines whether or notthe full standard error of difference matrix is returned.a list of length the number of classified tables, and named by the classify set.Each component is a logical scalar (default F) that determines whether or notthe full variance matrix of the predicted values is returned.6.2.1 An illustrationA simple example is the prediction of variety means from fitting model 2a (Section 4.2)to the NIN field trial data. Recall that a randomised block model with random replicateeffects is fitted to this data by:> rcb.asr rcb.pv rcb.pv$predictions$Variety$Variety$pvalsNotes:- Rep terms are ignored unless specifically included- mv is averaged over fixed levels- Variety is included in the prediction- (Intercept) is included in the prediction- mv is ignored in this predictionVariety predicted.value standard.error est.status1 ARAPAHOE 29.4375 3.855687 Estimable2 BRULE 26.0750 3.855687 Estimable3 BUCKSKIN 25.5625 3.855687 Estimable...54 TAM107 28.4000 3.855687 Estimable55 TAM200 21.2375 3.855687 Estimable56 VONA 23.6000 3.855687 Estimable$Variety$avsed[1] 4.979075The list orientated nature of predict.asreml() is potentially complex, particularly whenmore than one classified table is specified in a single function call. The principal reason forthis potential complexity lies in the fact that each predict.asreml() call requires at least onefurther iteration of the fitting routines (to construct the prediction design matrix). Forsituations where execution time is not limiting, it may be simpler to call predict.asreml()separately for each required classification table.To illustrate the potentially complex syntax of a predict function call, consider a hypotheticalexample where two predict tables are required, classified by factors (or compoundterms) ’A’ and ’B’. For the predictions classified by ’A’, present averaging is necessaryand the table of standard errors of difference is required. For those classified by ’B’, twomutually exclusive lists defining present averaging are required and we wish to weightthe cells of the first present hyper-table. The table of SED’s is not desired in this case.

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