tests/testthat/test-clm.R

In insight: Easy Access to Model Information for Various Model Objects

skip_if_not_installed("ordinal")

data(wine, package = "ordinal")
m1 <- ordinal::clm(rating ~ temp * contact, data = wine)

m2 <- suppressWarnings(ordinal::clm( # nominal + scale effects
  cyl ~ wt,
  scale = ~vs, nominal = ~hp,
  data = transform(mtcars, cyl = factor(cyl))
))

test_that("model_info", {
  expect_true(model_info(m1)$is_ordinal)
  expect_false(model_info(m1)$is_multinomial)
  expect_false(model_info(m1)$is_linear)
})

test_that("find_predictors", {
  expect_identical(find_predictors(m1), list(conditional = c("temp", "contact")))
  expect_identical(find_predictors(m1, flatten = TRUE), c("temp", "contact"))
  expect_null(find_predictors(m1, effects = "random"))
  expect_identical(
    find_predictors(m2),
    list(conditional = "wt", scale = "vs", nominal = "hp")
  )
})

test_that("find_random", {
  expect_null(find_random(m1))
})

test_that("get_random", {
  expect_warning(get_random(m1))
})

test_that("find_response", {
  expect_identical(find_response(m1), "rating")
})

test_that("get_response", {
  expect_equal(get_response(m1), wine$rating, tolerance = 1e-5)
})

test_that("get_predictors", {
  expect_identical(colnames(get_predictors(m1)), c("temp", "contact"))
})

test_that("link_inverse", {
  expect_equal(link_inverse(m1)(0.2), plogis(0.2), tolerance = 1e-5)
})

test_that("get_data", {
  expect_identical(nrow(get_data(m1)), 72L)
  expect_identical(colnames(get_data(m1)), c("rating", "temp", "contact"))
  expect_identical(colnames(get_data(m2)), c("cyl", "wt", "vs", "hp"))
})

test_that("find_formula", {
  expect_length(find_formula(m1), 1)
  expect_equal(
    find_formula(m1),
    list(conditional = as.formula("rating ~ temp * contact")),
    ignore_attr = TRUE
  )
  expect_equal(
    find_formula(m2),
    list(
      conditional = as.formula("cyl ~ wt"),
      scale = as.formula("~vs"),
      nominal = as.formula("~hp")
    ),
    ignore_attr = TRUE
  )
})

test_that("find_variables", {
  expect_identical(
    find_variables(m2),
    list(response = "cyl", conditional = "wt", scale = "vs", nominal = "hp")
  )
})

test_that("find_terms", {
  expect_equal(
    find_terms(m1),
    list(
      response = "rating",
      conditional = c("temp", "contact")
    ),
    ignore_attr = TRUE
  )
  expect_identical(
    find_terms(m1, flatten = TRUE),
    c("rating", "temp", "contact")
  )
  expect_identical(
    find_terms(m2),
    list(response = "cyl", conditional = "wt", scale = "vs", nominal = "hp")
  )
})

test_that("n_obs", {
  expect_equal(n_obs(m1), 72) # nolint
})

test_that("linkfun", {
  expect_false(is.null(link_function(m1)))
})

test_that("find_parameters", {
  expect_equal(
    find_parameters(m1),
    list(
      conditional = c(
        "1|2",
        "2|3",
        "3|4",
        "4|5",
        "tempwarm",
        "contactyes",
        "tempwarm:contactyes"
      )
    ),
    ignore_attr = TRUE
  )
  expect_identical(nrow(get_parameters(m1)), 7L)
  expect_identical(
    get_parameters(m1)$Parameter,
    c(
      "1|2",
      "2|3",
      "3|4",
      "4|5",
      "tempwarm",
      "contactyes",
      "tempwarm:contactyes"
    )
  )
})

test_that("is_multivariate", {
  expect_false(is_multivariate(m1))
})

test_that("find_statistic", {
  expect_identical(find_statistic(m1), "z-statistic")
})

test_that("get_predicted", {
  nd <- wine
  nd$rating <- NULL
  x <- as.data.frame(get_predicted(m1))
  y <- as.data.frame(get_predicted(m1, predict = NULL, type = "prob"))
  z <- predict(m1, type = "prob", newdata = nd, se.fit = TRUE)
  expect_true(all(c("Row", "Response", "Predicted", "SE") %in% colnames(x)))
  expect_equal(x, y, tolerance = 1e-5)
  for (i in 1:5) {
    expect_equal(x$Predicted[x$Response == i], unname(z$fit[, i]), ignore_attr = FALSE)
    expect_equal(x$SE[x$Response == i], unname(z$se.fit[, i]), ignore_attr = FALSE)
  }
  x <- as.data.frame(get_predicted(m1, predict = "classification"))
  y <- as.data.frame(get_predicted(m1, predict = NULL, type = "class"))
  z <- predict(m1, type = "class", newdata = nd)
  expect_equal(x, y, tolerance = 1e-5)
  expect_equal(as.character(x$Predicted), as.character(z$fit), ignore_attr = FALSE)

  # we use a hack to handle in-formula factors
  tmp <- wine
  tmp$rating <- as.numeric(tmp$rating)
  tmp <- ordinal::clm(factor(rating) ~ temp * contact, data = tmp)
  expect_s3_class(get_predicted(tmp), "get_predicted")
})