R/model_ordinal.R

In popiela/homework: Homework assignment

#' Create ordinal logistic regression
#' to measure likeliness to download mobile app
#' @param df
#'
#' @return
#' @export
#'
#' @examples
#' homework::model_ordinal(experiment_data)
model_ordinal <- function(df)
{

  model_data <- df %>%  dplyr::select(duration:answer) %>%  dplyr::mutate(answer = as.factor(answer) )

  model <- MASS::polr(answer ~ . , data = model_data, Hess=TRUE)

  coef_table <- coef(summary(model))
  p <- pnorm(abs(coef_table[, "t value"]), lower.tail = FALSE) * 2
  coef_table<- cbind(coef_table, "p_value" = p)

  coef_table <- tibble::as_tibble(coef_table, rownames = "Coef_name") %>%
    dplyr::arrange(desc(Coef_name)) %>%
    dplyr::slice(1:18) %>%
    dplyr::mutate(Odds_ratio = exp(Value)) %>%
    dplyr::arrange(p_value) %>%
    dplyr::rename(Coef_value = Value) %>%
    dplyr::select(Coef_name, Coef_value , p_value , Odds_ratio , everything())

  return(coef_table)
}