Add p-value column to tidy.lmodel2() (#592)

NEWS.md

@@ -39,6 +39,7 @@ TODO: sort out what happens to `glance.aov()`
 - `glance.biglm()` now returns a `df.residual` column
 - `tidy.htest()` column names are now run through `make.names()` to ensure syntactic correctness (#549 by @karissawhiting) (TODO: use tidyverse name repair?)
 - Many `glance()` methods now return the number of observations in a `nobs` column, which is typically the rightmost column.
+- `tidy.lmodel2()` now returns a `p.value` column (#570)
 
 ### Name changes for consistency
 

R/lmodel2-tidiers.R

@@ -7,6 +7,7 @@
 #' @evalRd return_tidy(
 #'   "term",
 #'   "estimate",
+#'   "p.value",
 #'   "conf.low",
 #'   "conf.high",
 #'   method = "Either OLS/MA/SMA/RMA"
@@ -17,6 +18,11 @@
 #'   (ordinary least squares), MA (major axis), SMA (standard major
 #'   axis), and RMA (ranged major axis).
 #'
+#'   The returned p-value is one-tailed and calculated via a permutation test.
+#'   A permutational test is used because distributional assumptions may not not
+#'   be valid. More information can be found in the vignette
+#'   (\code{\link{vignette("mod2user")}})
+#'
 #' @examples
 #' 
 #' library(lmodel2)
@@ -40,9 +46,9 @@
 #' @aliases lmodel2_tidiers
 #' @family lmodel2 tidiers
 tidy.lmodel2 <- function(x, ...) {
-  ret <- x$regression.results[1:3] %>%
-    select(method = Method, Intercept, Slope) %>%
-    tidyr::gather(term, estimate, -method) %>%
+  ret <- x$regression.results[c(1:3, 5)] %>%
+    select(method = Method, Intercept, Slope, p.value = quote("P-perm (1-tailed)")) %>%
+    tidyr::gather(term, estimate, -method, -p.value) %>%
     arrange(method, term)
 
   # add confidence intervals
@@ -54,7 +60,9 @@ tidy.lmodel2 <- function(x, ...) {
     select(method = Method, term, conf.low, conf.high)
 
   ret %>%
-    inner_join(confints, by = c("method", "term")) %>% 
+    inner_join(confints, by = c("method", "term")) %>%
+    # change column order so `p.value` is at the end
+    select(-p.value, dplyr::everything()) %>% 
     as_tibble()
 }
 

tests/testthat/test-lmodel2.R

@@ -17,7 +17,7 @@ test_that("lmodel2 tidier arguments", {
 test_that("tidy.lmodel2", {
   td <- tidy(fit)
   check_tidy_output(td)
-  check_dims(td, 8, 5)
+  check_dims(td, 8, 6)
 })
 
 test_that("glance.lmodel2", {