catdv_vs_dvprobs: Non-simulation based likelihood model diagnostic

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

Non-simulation based likelihood model diagnostic

Description

These plots attempt to provide a means of verifying that the estimated likelihoods and probabilities for categorical outcomes are captured within the model.

When the smooth spline is included (type includes "s"), it is expected that the overall trend is up and to the right; a relatively flat trend suggests that the modeled likelihood is inconsistent with the observed outcome.

Usage

catdv_vs_dvprobs(
  xpdb,
  mapping = NULL,
  cutpoint = 1,
  type = "vbs",
  title = "@y vs. @x | @run",
  subtitle = "Ofv: @ofv, Number of individuals: @nind",
  caption = "@dir",
  tag = NULL,
  xlab = c("probability", "basic"),
  facets,
  .problem,
  quiet,
  ...
)

Arguments

xpdb	<xp_xtras> or <xpose_data> object
mapping	ggplot2 style mapping
cutpoint	<numeric> Of defined probabilities, which one to use in plots.
type	See Details.
title	Plot title
subtitle	Plot subtitle
caption	Plot caption
tag	Plot tag
xlab	Either use the typical basic x-axis label (the cutpoint-defined column name) or label it based on the probability/likelihood it is estimating.
facets	Additional facets
.problem	Problem number
quiet	Silence extra debugging output
...	Any additional aesthetics.

Value

The desired plot

Examples

# Test M3 model
pkpd_m3 %>%
  # Need to ensure var types are set
  set_var_types(catdv=BLQ,dvprobs=LIKE) %>%
  # Set probs
  set_dv_probs(1, 1~LIKE, .dv_var = BLQ) %>%
  # Optional, but useful to set levels
  set_var_levels(1, BLQ = lvl_bin()) %>%
  # Plot with basic xlab makes no assumptions
  catdv_vs_dvprobs(xlab = "basic")

# Test categorical model
vismo_xpdb <- vismo_pomod  %>%
  set_var_types(.problem=1, catdv=DV, dvprobs=matches("^P\\d+$")) %>%
  set_dv_probs(.problem=1, 0~P0,1~P1,ge(2)~P23)

# Various cutpoints (note axes labels and texts)
vismo_xpdb %>%
  catdv_vs_dvprobs(xlab = "basic")
vismo_xpdb %>%
  catdv_vs_dvprobs(cutpoint = 2, xlab = "basic")
vismo_xpdb %>%
  catdv_vs_dvprobs(cutpoint = 3, xlab = "basic")

# Latter is arguably clearer with default xlab
vismo_xpdb %>%
  catdv_vs_dvprobs(cutpoint = 3)

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