| vpredict {asreml} | R Documentation |
Functions of variance components
Description
Calculates means and approximated standard errors from
functions of variance components from an asreml object.
Usage
vpredict(object, xform, ...)
Arguments
object |
An |
xform |
A two-sided formula, where the left-hand side labels the function name. The right-hand side defines the function to calculate as an algebraic expression. |
Details
The standard error of the computed value is approximated using the
Delta method with the function deriv(), which calculates
algebraic derivatives for a wide range of expressions. Any of the
variance components to be included in the function are
represented as: "V1", "V2", "V3", ... in the
order they appear in object$vparameters. Parentheses, and
simple functions like log, exp, sqrt are
also allowed. Results are always presented in sigma scale.
Value
A single-row data frame with components:
Estimate: The estimated value of the algebraic expression.SE: The estimated approximated standard error.