Given multivariable predictions and prediction (co)variances, calculate contrasts and their (co)variance
get.contr(data, gstat.object, X, ids = names(gstat.object$data))
a data frame containing for each row in data
the generalized
least squares estimates (named beta.1, beta.2, ...), their
variances (named var.beta.1, var.beta.2, ...) and covariances
(named cov.beta.1.2, cov.beta.1.3, ...)
data frame, output of predict
object of class gstat
, used to
extract ids; may be missing if ids
is used
contrast vector or matrix; the number of variables in
gstat.object
should equal the number of elements in X
if X
is a vector, or the number of rows in X
if X
is a matrix.
character vector with (selection of) id names, present in data
Edzer Pebesma
From data, we can extract the \(n \times 1\) vector with multivariable predictions, say $y$, and its \(n \times n\) covariance matrix $V$. Given a contrast matrix in $X$, this function computes the contrast vector $C=X'y$ and its variance $Var(C)=X'V X$.
predict