set_dv_probs: Set probability columns for categorical endpoints

In xpose.xtras: Extra Functionality for the 'xpose' Package

Set probability columns for categorical endpoints

Description

For categorical DVs or similar endpoints (such as censoring flag columns, like BLQ), this function allows probability columns to be defined for each level.

Usage

set_dv_probs(
  xpdb,
  .problem = NULL,
  ...,
  .dv_var = NULL,
  .handle_missing = c("quiet", "warn", "error")
)

Arguments

xpdb	<xp_xtras> object
.problem	<numeric> Problem number to use. Uses the all problems if NULL
...	Formulas where LHS are levels or pseudo-functions (see Details), and RHS are columns with probabilities of those levels.
.dv_var	<tidyselect> of column having the categorical observation. Default is first-listed catdv.
.handle_missing	<character> How to handle missing levels: "quiet", "warn", or "error"

Details

The same probability cannot be assigned to multiple values. Pseudo-functions can be used, or new columns can be created to overcome this limitation. The available pseudo-functions should be written like ge(value) (for >=), gt(value) (for >), etc. These comparison names are those used in Perl, Fortran and many other languages. The function eq() should not be used, but it will be ignored either way; equivalence is implied with the base syntax.

Value

<xp_xtras> object with updated probabilities

Examples

pkpd_m3 %>%
 # Not necessary, but correct to set var type before using this
 set_var_types(.problem=1, catdv=BLQ, dvprobs=LIKE) %>%
 # Set var type. Warnings can be helpful unless an inverse likelihood column is available
 set_dv_probs(.problem=1, 1~LIKE, .dv_var = BLQ, .handle_missing = "warn") %>%
 list_vars()

# Same as above with demo of inverse column
pkpd_m3 %>%
 xpose::mutate(INVLIKE = 1-LIKE) %>%
 set_var_types(.problem=1, catdv=BLQ, dvprobs=c(LIKE,INVLIKE)) %>%
 # Note no warning
 set_dv_probs(.problem=1, 1~LIKE, 0~INVLIKE, .dv_var = BLQ, .handle_missing = "warn")%>%
 list_vars()

# With categorical model
vismo_pomod  %>%
 # Update var types
 set_var_types(.problem=1, catdv=DV, dvprobs=matches("^P\\d+$")) %>%
 # Warning (as noted), does not recognize 3 is covered implicitly. That's ok!
 set_dv_probs(.problem=1, 0~P0,1~P1,ge(2)~P23, .handle_missing = "warn")%>%
 list_vars()

# Same as above, but...
vismo_pomod  %>%
 set_var_types(.problem=1, catdv=DV, dvprobs=matches("^P\\d+$")) %>%
 # Default is to not bother users with a warning
 set_dv_probs(.problem=1, 0~P0,1~P1,ge(2)~P23)%>%
 list_vars()

xpose.xtras documentation built on April 4, 2025, 2:13 a.m.