R/plot_actual_fitted.R

In dnepple/tprstats: TSB Statistics Package

#' Plot Actual Fitted
#'
#' Plots actual and fitted values of the dependent variable in a regression and 95% prediction interval. The horizontal axis is a sequence of integers denoting observations.
#'
#' @param linmod Linear model
#' @param MyData The data
#' @param col_name Name of column variable as a string (use quotes).
#' @export

plotActualFitted <- function(linmod, MyData, col_name) {
  Y <- unlist(MyData[, col_name])
  Observation <- seq(1, NROW(MyData))
  Pred_and_PI <- stats::predict(linmod, MyData, interval = "predict")
  Predicted <- Pred_and_PI[, 1]
  Lower <- Pred_and_PI[, 2]
  Upper <- Pred_and_PI[, 3]
  ymax <- max(Upper)
  ymin <- min(Lower)
  graphics::plot(Y ~ Observation,
    ylim = c(ymin, ymax), pch = 20,
    main = "Actual (black), Predicted (red), and 95% PI (blue)"
  )
  graphics::lines(Y ~ Observation)
  graphics::lines(Predicted ~ Observation, col = "red")
  graphics::lines(Upper ~ Observation, col = "blue")
  graphics::lines(Lower ~ Observation, col = "blue")
}