Check and manipulate the formula for a nonlinear model, such as
specified in nlmer.
nlformula(mc)a list with components
a response module of class "nlsResp"
the model frame, including a terms attribute
the fixed-effects model matrix
the random-effects terms object
matched call from the calling function, typically
nlmer(). Should have arguments named
a formula of the form resp ~ nlmod ~ meform
where resp is an expression for the response,
nlmod is the nonlinear model expression and
meform is the mixed-effects model formula.
resp can be omitted when, e.g., optimizing a design.
a data frame in which to evaluate the model function
either a numeric vector containing initial estimates for the nonlinear model parameters or a list with components
nlpars:the initial estimates of the nonlinear model parameters
theta:the initial estimates of the variance component parameters
The model formula for a nonlinear mixed-effects model is
of the form resp ~ nlmod ~ mixed where
resp is an expression (usually just a name) for
the response, nlmod is the call to the nonlinear
model function, and mixed is the mixed-effects
formula defining the linear predictor for the parameter
matrix. If the formula is to be used for optimizing
designs, the resp part can be omitted.
Other utilities: findbars,
mkRespMod, mkReTrms,
nobars, subbars