activePar {maxLik} | R Documentation |
Return a logical vector, indicating which parameters were free under
maximisation, as opposed to the fixed parameters that are treated as
constants. See argument “fixed” for maxNR
.
activePar(x, ...) ## Default S3 method: activePar(x, ...)
x |
object, created by a maximisation routine, or derived from a maximisation object. |
... |
further arguments for methods |
Several optimisation routines allow the user to fix some parameter values (or do it automatically in some cases). For gradient or Hessian based inference one has to know which parameters carry optimisation-related information.
A logical vector, indicating whether the parameters were free to change during optimisation algorithm.
Ott Toomet
# a simple two-dimensional exponential hat f <- function(a) exp(-a[1]^2 - a[2]^2) # # maximize wrt. both parameters free <- maxNR(f, start=1:2) summary(free) # results should be close to (0,0) activePar(free) # keep the first parameter constant cons <- maxNR(f, start=1:2, fixed=c(TRUE,FALSE)) summary(cons) # result should be around (1,0) activePar(cons)