drmc {drc}

Sets control arguments

Description

Set control arguments in the control argument in the function 'drm'.

Usage

  drmc(constr = FALSE, errorm = TRUE, maxIt = 500, method="BFGS", 
  noMessage = FALSE, relTol = 1e-07, rmNA=FALSE, useD = FALSE, 
  trace = FALSE, otrace = FALSE, warnVal = -1, dscaleThres = 1e-15, rscaleThres = 1e-15)

Arguments

constr

logical. If TRUE optimisation is constrained, only yielding non-negative parameters.

errorm

logical specifying whether failed convergence in drm should result in an error or only a warning.

maxIt

numeric. The maximum number of iterations in the optimisation procedure.

method

character string. The method used in the optimisation procedure. See optim for available methods.

noMessage

logical, specifying whether or not messages should be displayed.

relTol

numeric. The relative tolerance in the optimisation procedure.

rmNA

logical. Should NAs be removed from sum of squares used for estimation? Default is FALSE (not removed).

useD

logical. If TRUE derivatives are used for estimation (if available).

trace

logical. If TRUE the trace from optim is displayed.

otrace

logical. If TRUE the output from optim is displayed.

warnVal

numeric. If equal to 0 then the warnings are stored and displayed at the end. See under 'warn' in options. The default results in suppression of warnings.

dscaleThres

numeric value specifying the threshold for dose scaling.

rscaleThres

numeric value specifying the threshold for response scaling.

Value

A list with 8 components, one for each of the above arguments.

Note

The use of a non-zero constant bcAdd may in some cases make it more difficult to obtain convergence of the estimation procedure.

Author(s)

Christian Ritz

Examples

### Displaying the default settings
drmc()  

### Using 'method' argument
model1 <- drm(ryegrass, fct = LL.4())

model2 <- drm(ryegrass, fct = LL.4(),
control = drmc(method = "Nelder-Mead"))