drc (version 1.6-0)

vcov.drc: Calculating variance-covariance matrix for objects of class 'drc'

Description

'vcov' returns the estimated variance-covariance matrix for the parameters in the non-linear function.

Usage

## S3 method for class 'drc':
vcov(object, ..., corr = FALSE)

Arguments

object

an object of class 'drc'.

...

additional arguments.

corr

logical. If TRUE a correlation matrix is returned.

Value

• A matrix of estimated variances and covariances.

Examples

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