spaMM (version 1.7.2)

update.HLfit: Updates an HLCor or HLfit fit

Description

update will update and (by default) re-fit a model. It does this mostly by extracting the call stored in the object, updating the call and evaluating that call. (however, currently the predictor argument is processed differently).

Usage

## S3 method for class 'HLfit':
update(object, formula., ..., evaluate = TRUE)

Arguments

object

A return object from an HLfit call.

formula.

Changes to the formula. Beware of the syntax: see update.formula for details.

...

Additional arguments to the call, or arguments with changed values. Use name = NULL to remove the argument name.

evaluate

If TRUE, evaluate the new call else return the call.

Value

• An HLCor or HLfit fit of the same type as the input object.

See Also

See also HLCor, HLfit.

Examples

data(wafers)
## First the fit to be updated:
wFit <- HLfit(y ~X1*X3+X2*X3+I(X2^2)+(1|batch),family=Gamma(log),
          resid.formula = ~ X3+I(X3^2) ,data=wafers)

# For estimates given by Lee et al., Appl. Stochastic Models Bus. Ind. (2011) 27:  315-328:
# Refit with given beta or/and phi values:
 
betavals <- c(5.55,0.08,-0.14,-0.21,-0.08,-0.09,-0.09)
# reconstruct fitted phi value from predictor for log(phi)
Xphi <- with(wafers,cbind(1,X3,X3^2)) ## design matrix
phifit <- exp(Xphi %*% c(-2.90,0.1,0.95))
update(wFit,formula.= . ~ offset(wFit$`X.pv` %*% betavals)+(1|batch),
       ranFix=list(lambda=exp(-3.67),phi=phifit))

## There are subtlety in performing REML fits of constrained models: 
update(wFit,formula.= . ~ offset(wFit$`X.pv` %*% betavals)+(1|batch))
## ... changes the REML correction. Consider instead
update(wFit,formula.= . ~ offset(wFit$`X.pv` %*% betavals)+(1|batch),
       REMLformula=wFit$predictor)
## Alternatively, show original wFit as differences from betavals:  
update(wFit,formula.= . ~ . +offset(wFit$`X.pv` %*% betavals))