R: Visually check outliers (dot plot)

plot_outliers {rempsyc}

R Documentation

Visually check outliers (dot plot)

Description

Easily and visually check outliers through a dot plot with accompanying reference lines at +/- 3 MAD or SD. When providing a group, data are group-mean centered and standardized (based on MAD or SD); if no group is provided, data are simply standardized.

Usage

plot_outliers(
  data,
  group = NULL,
  response,
  method = "mad",
  criteria = 3,
  colours,
  xlabels = NULL,
  ytitle = NULL,
  xtitle = NULL,
  has.ylabels = TRUE,
  has.xlabels = TRUE,
  ymin,
  ymax,
  yby = 1,
  ...
)

Arguments

`data`	The data frame.
`group`	The group by which to plot the variable.
`response`	The dependent variable to be plotted.
`method`	Method to identify outliers, either (e.g., 3) median absolute deviations ("mad", default) or standard deviations ("sd").
`criteria`	How many MADs (or standard deviations) to use as threshold (default is 3).
`colours`	Desired colours for the plot, if desired.
`xlabels`	The individual group labels on the x-axis.
`ytitle`	An optional y-axis label, if desired.
`xtitle`	An optional x-axis label, if desired.
`has.ylabels`	Logical, whether the x-axis should have labels or not.
`has.xlabels`	Logical, whether the y-axis should have labels or not.
`ymin`	The minimum score on the y-axis scale.
`ymax`	The maximum score on the y-axis scale.
`yby`	How much to increase on each "tick" on the y-axis scale.
`...`	Other arguments passed to ggplot2::geom_dotplot.

Value

A dot plot of class ggplot, by group.

Examples


# Make the basic plot
plot_outliers(
  airquality,
  group = "Month",
  response = "Ozone"
)

plot_outliers(
  airquality,
  response = "Ozone",
  method = "sd"
)