n_ind for coxph and fix deprecated function of marginaleffect

NEWS.md

@@ -5,6 +5,8 @@
 - new argument `model_matrix_attr` in `tidy_and_attach()` and `tidy_plus_plus()`
   to attach model frame and model matrix to the model as attributes for saving
   some execution time (#254)
+- `tidy_add_n()` now returns `n_ind` the number of individuals, in addition to
+  the number of observations (#251)
 - by default, `tidy_parameters()` calls now `parameters::model_parameters()`
   with `pretty_names = FALSE` for saving execution time (#259)
 

R/broom.helpers-package.R

@@ -53,7 +53,7 @@ utils::globalVariables(c(".", "where"))
           "y.level", "component", "term", "original_term", "variable",
           "var_label", "var_class", "var_type",
           "var_nlevels", "header_row", "contrasts", "contrasts_type",
-          "reference_row", "label", "n_obs", "n_event", "exposure"
+          "reference_row", "label", "n_obs", "n_ind", "n_event", "exposure"
         )
       ),
       dplyr::everything()
@@ -67,7 +67,7 @@ utils::globalVariables(c(".", "where"))
     names(.attributes),
     c(
       "exponentiate", "conf.level", "coefficients_type", "coefficients_label",
-      "variable_labels", "term_labels", "N_obs", "N_event", "Exposure",
+      "variable_labels", "term_labels", "N_obs", "N_ind", "N_event", "Exposure",
       "force_contr.treatment", "skip_add_reference_rows",
       "find_missing_interaction_terms", "component"
     )

R/model_get_n.R

@@ -6,16 +6,17 @@
 #' For Poisson models, will return the number of events and exposure time
 #' (defined with [stats::offset()]).
 #'
-#' For Cox models ([survival::coxph()]), will return the number of events and
-#' exposure time.
+#' For Cox models ([survival::coxph()]), will return the number of events,
+#' exposure time and the number of individuals.
 #'
 #' For competing risk regression models ([tidycmprsk::crr()]), `n_event` takes
 #' into account only the event of interest defined by `failcode.`
 #'
 #' See [tidy_add_n()] for more details.
 #'
-#' The total number of observations (`N_obs`), of events (`N_event`) and of
-#' exposure time (`Exposure`) are stored as attributes of the returned tibble.
+#' The total number of observations (`N_obs`), of individuals (`N_ind`), of
+#' events (`N_event`) and of exposure time (`Exposure`) are stored as attributes
+#' of the returned tibble.
 #'
 #' This function does not cover `lavaan` models (`NULL` is returned).
 #'
@@ -193,6 +194,15 @@ model_get_n.coxph <- function(model) {
   )
   attr(n, "N_obs") <- sum(w)
 
+  mf <- stats::model.frame(model) # using stats::model.frame() to get (id)
+  if (!"(id)" %in% names(mf))
+    mf[["(id)"]] <- seq_len(nrow(mf))
+  n_obs_per_ind <- mf %>%
+    dplyr::add_count(dplyr::pick("(id)")) |>
+    dplyr::pull("n")
+  n$n_ind <- colSums(tcm * w / n_obs_per_ind)
+  attr(n, "N_ind") <- sum(w / n_obs_per_ind)
+
   y <- model %>% model_get_response()
   status <- y[, ncol(y)]
   if (ncol(y) == 3) {

R/tidy_add_n.R

@@ -40,10 +40,11 @@
 #' obtained with `n_event / exposure`.
 #'
 #' For Cox models ([survival::coxph()]), an individual could be coded
-#' with several observations (several rows). `n_obs` will correspond to the weighted
-#' number of observations which could be different from the number of
-#' individuals. `tidy_add_n()` will also compute a (weighted) number of events
-#' (`n_event`) according to the definition of the [survival::Surv()] object.
+#' with several observations (several rows). `n_obs` will correspond to the
+#' weighted number of observations which could be different from the number of
+#' individuals `n_ind`. `tidy_add_n()` will also compute a (weighted) number of
+#' events (`n_event`) according to the definition of the [survival::Surv()]
+#' object.
 #' Exposure time is also returned in `exposure` column. It is equal to the
 #' (weighted) sum of the time variable if only one variable time is passed to
 #' [survival::Surv()], and to the (weighted) sum of `time2 - time` if two time
@@ -52,9 +53,9 @@
 #' For competing risk regression models ([tidycmprsk::crr()]), `n_event` takes
 #' into account only the event of interest defined by `failcode.`
 #'
-#' The (weighted) total number of observations (`N_obs`), of events (`N_event`) and
-#' of exposure time (`Exposure`) are stored as attributes of the returned
-#' tibble.
+#' The (weighted) total number of observations (`N_obs`), of individuals
+#' (`N_ind`), of events (`N_event`) and of exposure time (`Exposure`) are
+#' stored as attributes of the returned tibble.
 #'
 #' @param x a tidy tibble
 #' @param model the corresponding model, if not attached to `x`
@@ -140,6 +141,9 @@ tidy_add_n <- function(x, model = tidy_get_model(x)) {
   if (!is.null(attr(n, "N_obs"))) {
     .attributes$N_obs <- attr(n, "N_obs")
   }
+  if (!is.null(attr(n, "N_ind"))) {
+    .attributes$N_ind <- attr(n, "N_ind")
+  }
   if (!is.null(attr(n, "N_event"))) {
     .attributes$N_event <- attr(n, "N_event")
   }

tests/testthat/test-add_n.R

@@ -174,7 +174,9 @@ test_that("tidy_add_n() works with survival::coxph", {
   skip_on_cran()
   df <- survival::lung %>% dplyr::mutate(sex = factor(sex))
   mod <- survival::coxph(survival::Surv(time, status) ~ ph.ecog + age + sex, data = df)
-  expect_error(mod %>% tidy_and_attach() %>% tidy_add_n(), NA)
+  expect_error(res <- mod %>% tidy_and_attach() %>% tidy_add_n(), NA)
+  expect_equivalent(res$n_ind, c(227, 227, 90))
+  expect_equivalent(attr(res, "N_ind"), 227)
 })
 
 test_that("tidy_add_n() works with survival::survreg", {

tests/testthat/test-model_get_n.R

@@ -240,7 +240,10 @@ test_that("model_get_n() works with survival::coxph", {
   df <- survival::lung %>% dplyr::mutate(sex = factor(sex))
   mod <- survival::coxph(survival::Surv(time, status) ~ ph.ecog + age + sex, data = df)
   expect_error(res <- mod %>% model_get_n(), NA)
-  expect_equivalent(names(res), c("term", "n_obs", "n_event", "exposure"))
+  expect_equivalent(
+    names(res),
+    c("term", "n_obs", "n_ind", "n_event", "exposure")
+  )
 
   test <- list(
     start = c(1, 2, 5, 2, 1, 7, 3, 4, 8, 8),
@@ -250,8 +253,12 @@ test_that("model_get_n() works with survival::coxph", {
   )
   mod <- survival::coxph(survival::Surv(start, stop, event) ~ x, test)
   expect_error(res <- mod %>% model_get_n(), NA)
-  expect_equivalent(names(res), c("term", "n_obs", "n_event", "exposure"))
+  expect_equivalent(
+    names(res),
+    c("term", "n_obs", "n_ind", "n_event", "exposure")
+  )
   expect_equivalent(res$n_obs, c(10, 10))
+  expect_equivalent(res$n_ind, c(10, 10))
   expect_equivalent(res$n_event, c(7, 7))
   expect_equivalent(res$exposure, c(43, 43))
 })
@@ -264,7 +271,10 @@ test_that("model_get_n() works with survival::survreg", {
     dist = "exponential"
   )
   expect_error(res <- mod %>% model_get_n(), NA)
-  expect_equivalent(names(res), c("term", "n_obs", "n_event", "exposure"))
+  expect_equivalent(
+    names(res),
+    c("term", "n_obs", "n_ind", "n_event", "exposure")
+  )
 })
 
 test_that("model_get_n() works with nnet::multinom", {
@@ -401,7 +411,10 @@ test_that("model_get_n() works with tidycmprsk::crr", {
   skip_on_cran()
   skip_if_not_installed("tidycmprsk")
 
-  mod <- tidycmprsk::crr(Surv(ttdeath, death_cr) ~ age + grade, tidycmprsk::trial)
+  mod <- tidycmprsk::crr(
+    survival::Surv(ttdeath, death_cr) ~ age + grade,
+    tidycmprsk::trial
+  )
   res <- mod %>% tidy_plus_plus()
   expect_equivalent(
     res$n_event,

vignettes/tidy.Rmd

@@ -308,6 +308,7 @@ tibble::tribble(
   "label", "`tidy_add_term_labels()`", "String of term labels based on (1) labels provided in `labels` argument if provided; (2) factor levels for categorical variables coded with treatment, SAS or sum contrasts; (3) variable labels when there is only one term per variable; and (4) term name otherwise.<br /><em>Require \"variable_label\" column. If needed, will automatically apply `tidy_add_variable_labels()`.<br />Require \"contrasts\" column. If needed, will automatically apply `tidy_add_contrasts()`.</em>",
   "header_row", "`tidy_add_header_rows()`", "Logical indicating if a row is a header row for variables with several terms. Is equal to `NA` for variables who do not have an header row.</br><em>Require \"label\" column. If needed, will automatically apply `tidy_add_term_labels()`.<br />It is better to apply `tidy_add_header_rows()` after other `tidy_*` functions</em>",
   "n_obs", "`tidy_add_n()`", "Number of observations",
+  "n_ind", "`tidy_add_n()`", "Number of individuals (for Cox models)",
   "n_event", "`tidy_add_n()`", "Number of events (for binomial and multinomial logistic models, Poisson and Cox models)",
   "exposure", "`tidy_add_n()`", "Exposure time (for Poisson and Cox models)"
 ) %>%
@@ -346,6 +347,7 @@ tibble::tribble(
   "Custom term labels passed to `tidy_add_term_labels()`",
   "N_obs", "`tidy_add_n()`", "Total number of observations",
   "N_event", "`tidy_add_n()`", "Total number of events",
+  "N_ind", "`tidy_add_n()`", "Total number of individuals (for Cox models)",
   "Exposure", "`tidy_add_n()`", "Total of exposure time",
   "component", "`tidy_zeroinfl()`", "`component` argument passed to `tidy_zeroinfl()`"
 ) %>%