This utility function prepares tidy choice data (without x) for fast data access.

vd_prepare_nox(dt, Af = NULL)

Arguments

dt

tidy choice data (columns: id, task, alt, p, attributes)

Af

(optional) contains a full design matrix (for attribute-based screening), or, more generally, a design matrix used for attribute-based screening

Value

list containing information for prediction functions

Details

Note: This function is only exported because it makes it easier to tinker with this package. This function re-arranges choice data for fast access, mainly for demand prediction.

Examples

#Minimal example:
#One attribute with 3 levels, 2 subjects, 3 alternatives, 2 tasks
dt <- structure(list(id = c(1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 
                            2L, 2L), 
                     task = c(1L, 1L, 1L, 2L, 2L, 2L, 1L, 1L, 1L, 2L, 2L, 2L), 
                     alt = c(1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L), 
                     x = c(1, 0, 2, 1, 0, 1, 2, 3, 1, 1, 0, 1), 
                     p = c(0, 1, 1, 1, 2, 0, 2, 2, 1, 2, 1, 1), 
                     attr2 = c(1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0), 
                     attr1 = c(0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 1, 1)), 
                 class = c("tbl_df", "tbl", "data.frame"), row.names = c(NA,-12L))
test <- dt %>% dplyr::select(-all_of("x")) %>% vd_prepare_nox()