Returns a list of optimization controls used in
Rdistance and provides a way to change them if needed.
optimizer = "nlminb",
evalMax = 2000,
maxIters = 1000,
likeTol = 1e-08,
coefTol = 1.5e-08,
hessEps = 1e-08,
requireUnits = TRUE,
maxBSFailPropForWarning = 0.2,
contrasts = NULL
A string specifying the optimizer
to use. Results
vary between optimizers, so switching algorithms sometimes
makes a poorly behaved distance function converge. The valid
values are "optim" which uses
The maximum number of objective function evaluations allowed.
The maximum number of optimization iterations allowed.
The maximum change in the likelihood (the objective) between iterations that is tolerated during optimization. If the likelihood changes by less than this amount, optimization stops and a solution is declared.
The maximum change in the model coefficients between iterations that is tolerated during optimization. If the sum of squared coefficient differences changes by less than this amount between iterations, optimization stops and a solution is declared.
A vector of parameter distances used during
computation of numeric second derivatives. Should have length
1 or the number of parameters in the model. See function
A logical specifying whether measurement
units are required on distances and areas. If TRUE,
measurement units are required on off-transect and radial
distances in the input data frame. Likewise, measurement
units are required on transect length and study area size.
Assign units with statement like
The proportion of bootstrap iterations that can fail without a warning. If the proportion of bootstrap iterations that did not converge exceeds this parameter, a warning about the validity of CI's is issued in the print method for abundance objects.
A list, whose entries are values (numeric matrices, functions or character strings naming functions) to be used as replacement values for the default contrasts function and whose names are the names of columns of data containing factors.
There are several ways to change the contrasts used for factors
in Rdistance because all methods used in linear models (
A list containing named components for each of the controls. This list has the same components as this function has input parameters.
# increase number of iterations
# change optimizer and decrease tolerance
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.