optimizers {sem} | R Documentation |
These functions call optimizers (nlm
, optim
, or nlminb
),
to fit structural equation models, and are called by the sem
function.
The user would not normally call these functions directly, but rather supply one of them in the optimizer
argument to
sem
. Users may also write them own optimizer functions.
optimizerNlm(start, objective=objectiveML, gradient=TRUE, maxiter, debug, par.size, model.description, warn, ...) optimizerOptim(start, objective=objectiveML, gradient=TRUE, maxiter, debug, par.size, model.description, warn, method="CG", ...) optimizerNlminb(start, objective=objectiveML, gradient=TRUE, maxiter, debug, par.size, model.description, warn, ...)
start |
a vector of start values for the parameters. |
objective |
the objective function to be optimized; see objective.functions. |
gradient |
|
maxiter |
the maximum number of iterations allowed. |
debug |
|
par.size |
|
model.description |
a list with elements describing the structural-equation model (see the code for details). |
warn |
if |
method |
the method to be employed by the |
... |
additional arguments for the |
An object of class "semResult"
, with elements:
convergence |
|
iterations |
the number of iterations required. |
par |
the vector of parameter estimates. |
vcov |
the estimated covariance matrix of the parameter estimates, based on a numeric Hessian; not supplied by |
criterion |
the optimized value of the objective function. |
C |
the model-implied covariance or moment matrix at the parameter estimates. |
A |
the estimated A matrix. |
P |
the estimated P matrix. |
John Fox jfox@mcmaster.ca
sem
, objective.functions
, nlm
, optim
, nlminb