From ffeb30082dd6015a93cec66efd6bfa422641bf11 Mon Sep 17 00:00:00 2001
From: emse-p4a-gwu <john.helveston@gmail.com>
Date: Sun, 19 Feb 2023 06:39:55 -0500
Subject: [PATCH] add comment to predict

---
 R/predict.R | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/R/predict.R b/R/predict.R
index c62f646..92334a0 100644
--- a/R/predict.R
+++ b/R/predict.R
@@ -127,7 +127,7 @@ predict.logitr <- function(
 formatNewData <- function(object, newdata, obsID) {
   inputs <- object$inputs
   newdata <- as.data.frame(newdata) # tibbles break things
-  newdata <- adjustFactorLevels(object, newdata) # if missing factor levels
+  newdata <- checkFactorLevels(object, newdata)
   recoded <- recodeData(newdata, inputs$pars, inputs$randPars)
   X <- recoded$X
   predictParCheck(object, X) # Check if model pars match those from newdata
@@ -145,7 +145,11 @@ formatNewData <- function(object, newdata, obsID) {
   return(list(X = X, scalePar = scalePar, obsID = obsID))
 }
 
-adjustFactorLevels <- function(object, newdata) {
+# If some factor levels present in the data used to estimate the model
+# are missing, then they need to be added back into the newdata so that
+# the coefficients are correctly interpreted. This function adds back
+# missing factor levels
+checkFactorLevels <- function(object, newdata) {
   levels_orig <- object$data$factorLevels
   factorLevels <- getFactorLevels(newdata, object$inputs$pars)
   if (length(factorLevels) > 0) {