ASReml-S reference manual - VSN International

covG.paramR.parampredictconstraintssubsetfamilyweights3.7 The asreml function call 25a formula object, specifying the error structure of the model, withthe terms, separated by + operators, on the right of a ∼ operator.This argument has the same general characteristics as fixed, but therewill be no left side to the ∼ expression. The default is the keywordunits which is defined as factor(seq(1,nrow(data))) and included inthe model frame. A variance model for the residual component of themodel can be specified using special functions described below.a list object, generated by a call to asreml.gdflt using the random formula,representing variance structures of random terms of the modelto hold initial parameter estimates and constraints.a list object, generated by a call to asreml.rdflt using the rcov formula,representing the error structure of the model to hold initial parameterestimates and constraints.a list object of length the number of predict tables (the length ofthe classify vector) and named by the classifying terms where eachelement is in turn a list with components pvals, sed, vcov and avsed.a matrix specifying constraints among the variance components withas many rows as there are variance parameters and as many columnsas there are constraints (see below).a logical vector identifying which subset of the rows of the data shouldbe used in the fit. All observations are included by default.family object - a list of functions and expressions for defining thelink and variance functions. This option is under development andcurrently only gaussian with an identity link function is supportedvia the asreml family function asreml.gaussian(). In addition to thelink argument, this function takes an additional dispersion argumentas in asreml.gaussian(link=”identity”,dispersion=NA). The default forasreml.gaussian() is NA which implies that asreml will estimate theparameter, otherwise asreml will fix the parameter at the nominatedvalue.character string or name identifying the column of data to use asweights in the fit.offset character string or name identifying the column of data toinclude as an offset in the model. This is ignored if family=gaussian(link=”identity”).na.method.Ycharacter string to control filtering of missing data in the response.Possible values are "include" (the default), "omit" and "fail". Thisis applied to the model.frame after any subset argument has beenused. The default ("include") is to estimate missing values; thismay be necessary in spatial models to preserve the spatial structure.The value "omit" deletes observations that contain missing values inthe response variate, but missing values in covariates may be retaineddepending on na.method.X.