Extract response values, observation weights, and offsets

A helper function for extracting response values, observation weights, and offsets from a dataset. It is designed for use in the extract_model_data function of custom reference model objects (see init_refmodel()).

Usage

y_wobs_offs(newdata, wrhs = NULL, orhs = NULL, resp_form)

Arguments

newdata

The data.frame from which at least the response values should be extracted.

wrhs

Either a right-hand side formula consisting only of the variable in newdata containing the weights, NULL (for using a vector of ones), or directly the numeric vector of observation weights.

orhs

Either a right-hand side formula consisting only of the variable in newdata containing the offsets, NULL (for using a vector of zeros), or directly the numeric vector of offsets.

resp_form

If this is a formula, then the second element of this formula (if the formula is a standard formula with both left-hand and right-hand side, then its second element is the left-hand side; if the formula is a right-hand side formula, then its second element is the right-hand side) will be extracted from newdata (so resp_form may be either a standard formula or a right-hand side formula, but in the latter case, the right-hand side should consist only of the response variable). In all other cases, NULL will be returned for element y of the output list.

Value

A list with elements y, weights, and offset, each being a numeric vector containing the data for the response, the observation weights, and the offsets, respectively. An exception is that y may also be NULL (depending on argument resp_form), a non-numeric vector, or a factor.

See also

init_refmodel()