1### methods for extracting standard errors from the models
2
3stdEr <- function(x, ...)
4    ## Extract standard deviations from models (as coefficients)
5    UseMethod("stdEr")
6
7stdEr.default <- function(x, ...) {
8   if( !isS4( x ) ) {
9      if( !is.null( x$std ) ) {
10         return(x$std)
11      }
12   }
13   if(!is.null(vc <- vcov(x))) {
14      s <- sqrt(diag(vc))
15      names(s) <- names(coef(x))
16      return(s)
17   }
18   return(NULL)
19                           # if neither std nor vcov is defined, we return NULL...
20}
21
22stdEr.lm <- function(x, ...)
23    sqrt(diag(vcov(x)))
24
25