R/oneway.R

In acolorado1/oneway: One-way Analysis of Variance

#' One Way Analysis of Variance
#'
#' oneway computes a one-way analysis of variance
#' and includes group level summary statistics
#'
#' @param formula an object of class formula relating the
#' dependent variable to the grouping variable.
#' @param data a data frame containing the varibles in the model.
#' @import dplyr
#' @export
#'
#' @return a list with two elements.
#' @examples
#' mileage <- oneway(mpg ~ cyl, mtcars)
oneway <- function(formula, data){
  #delete missing data
  data <- na.omit(data)

  #ANOVA
  fit <- lm(formula, data)

  #summary statistics
  group <- as.character(formula[[3]])
  y <- as.character(formula[[2]])
  stats <- data %>%
      group_by(.data[[group]])%>%
      summarise(n = n(),
                mean = mean(.data[[y]]),
                sd = sd(.data[[y]]))%>%
      as.data.frame()



  #return results
  result <- list(anova = fit, summarystats = stats)
  class(result) <- "oneway"
  return(result)

}