tests/testthat/test-betareg.R

In parameters: Processing of Model Parameters

skip_if_not_installed("betareg")

test_that("betareg", {
  data("GasolineYield", package = "betareg")
  data("FoodExpenditure", package = "betareg")

  m1 <- betareg::betareg(yield ~ batch + temp, data = GasolineYield)
  m2 <- betareg::betareg(I(food / income) ~ income + persons, data = FoodExpenditure)

  # ci
  expect_equal(ci(m1)$CI_low, as.vector(confint(m1)[, 1]), tolerance = 1e-4)
  expect_equal(ci(m2)$CI_low, as.vector(confint(m2)[, 1]), tolerance = 1e-4)

  # se
  s <- summary(m1)
  expect_equal(
    standard_error(m1)$SE,
    as.vector(c(s$coefficients$mean[, 2], s$coefficients$precision[, 2])),
    tolerance = 1e-4
  )
  s <- summary(m2)
  expect_equal(
    standard_error(m2)$SE,
    as.vector(c(s$coefficients$mean[, 2], s$coefficients$precision[, 2])),
    tolerance = 1e-4
  )

  # p-values
  expect_equal(
    p_value(m1)$p,
    c(0, 0, 0, 0, 0, 0, 0, 0, 1e-05, 0.00114, 0, 6e-05),
    tolerance = 1e-3
  )
  expect_equal(p_value(m2)$p, c(0.00542, 5e-05, 8e-04, 1e-05), tolerance = 1e-3)

  # check vcov args
  expect_message({
    out <- model_parameters(m1, vcov = "vcovHAC")
  })
  expect_equal(out$SE, unname(coef(summary(m1))[[1]][, 2]), tolerance = 1e-3)

  # model parameters
  expect_equal(
    model_parameters(m1)$Coefficient,
    as.vector(coef(m1))[1:11],
    tolerance = 1e-4
  )
  expect_equal(
    model_parameters(m1, component = "all")$Coefficient,
    as.vector(coef(m1)),
    tolerance = 1e-4
  )
  expect_equal(
    model_parameters(m2)$Coefficient,
    c(-0.62255, -0.0123, 0.11846),
    tolerance = 1e-4
  )
  expect_equal(
    model_parameters(m2, component = "all")$Coefficient,
    c(-0.62255, -0.0123, 0.11846, 35.60975033),
    tolerance = 1e-4
  )
})