uscale {eba} | R Documentation |
Extract the (normalized) utility scale for an elimination-by-aspects (EBA) model.
uscale(object, norm = "sum", log = FALSE)
object |
an object of class |
norm |
either |
log |
should the log of the utility scale values be returned? Defaults to FALSE. |
Each utility scale value is defined as the sum of aspect values (EBA model parameters) that characterize a given stimulus. First these sums are computed for all stimuli, then normalization (if any) is applied. As each type of normalization corresponds to a multiplication by a positive real number, the ratio between scale values remains constant.
The (normalized) utility scale of the stimuli.
data(drugrisk)
A <- list(c(1), c(2,7), c(3,7), c(4,7,8), c(5,7,8), c(6,7,8))
eba1 <- eba(drugrisk[, , group = "male30"], A) # EBA model
uscale(eba1) # sum-to-unity normalization
uscale(eba1, norm=1) # u(alcohol) := 1
uscale(eba1, norm=5) # u(heroine) := 1
uscale(eba1, norm=NULL) # no normalization
uscale(eba1, norm=1, log=TRUE) # log utility scale, log u(alcohol) := 0