tests/testthat/test-mean.R

In fable: Forecasting Models for Tidy Time Series

context("test-mean")

test_that("MEAN", {
  fit <- USAccDeaths_tbl %>% model(mean = MEAN(value))
  expect_identical(
    fitted(fit) %>% select(index, .fitted),
    USAccDeaths_tbl %>% transmute(.fitted = mean(value))
  )

  expect_equivalent(
    glance(fit)$sigma2, var(scale(USAccDeaths_tbl$value, scale = FALSE))
  )

  expect_identical(
    residuals(fit)[[".resid"]], USAccDeaths_tbl$value - mean(USAccDeaths_tbl$value)
  )

  expect_identical(
    tidy(fit)$estimate, mean(USAccDeaths_tbl$value)
  )

  expect_output(report(fit), "Mean: 8788\\.7917")

  fc <- fit %>% forecast(h = 3)

  expect_identical(
    fc_mean(fc$value),
    rep(mean(USAccDeaths_tbl$value), 3)
  )

  fc_sim <- fit %>% forecast(h = 3, bootstrap = TRUE, times = 5)

  # expect_identical(
  #   fc$value, fc_sim$value
  # )
})