Extracting residuals from the fitted dose-response model

residuals extracts different types of residuals from an object of class 'drc'.

Usage

# S3 method for class 'drc'
residuals(
  object,
  typeRes = c("working", "standardised", "studentised"),
  trScale = TRUE,
  ...
)

Arguments

object

an object of class 'drc'.

typeRes

character string specifying the type of residual to be returned: raw/working residuals, residuals standardised using the estimated residual standard error, or studentised residuals based on the H matrix of partial derivatives of the model function.

trScale

logical value indicating whether or not to return residuals on the transformed scale (in case a Box-Cox transformation was applied).

...

additional arguments.

Value

The raw (also called working) residuals or some kind of scaled residuals extracted from object.

Author

Christian Ritz

Examples

## Fitting a four-parameter log-logistic model
ryegrass.m1 <- drm(rootl ~ conc, data = ryegrass, fct = LL.4())

## Displaying the residual plot (raw residuals)
plot(fitted(ryegrass.m1), residuals(ryegrass.m1))


## Using the standardised residuals
plot(fitted(ryegrass.m1), residuals(ryegrass.m1, typeRes = "standard"))