Empirical cumulative distribution function (ECDF) plot

Draws the empirical CDF of a numeric variable (the proportion of observations at or below each value), optionally split by a grouping variable. Unlike a histogram it needs no bin-width choice and makes quantiles, medians and group shifts easy to read directly off the curve.

Usage

ecdf_plot(
  data,
  x,
  group = NULL,
  reference_quantiles = NULL,
  palette = NULL,
  legend_inside = FALSE,
  title = NULL,
  x_lab = NULL,
  y_lab = "Cumulative proportion"
)

Arguments

data

A data frame.

x

The numeric variable (string or unquoted name).

group

Optional grouping variable (string or unquoted name) mapped to colour, giving one ECDF per group.

reference_quantiles

Optional numeric vector of probabilities in [0, 1] to mark with light horizontal guides (e.g. c(0.25, 0.5, 0.75)); NULL (the default) draws none.

palette

Colours for the groups; defaults to depictr_palette().

legend_inside

When TRUE (and a group is given), draw the legend inside the panel (in the bottom-right corner the ECDF leaves empty once it saturates) over a translucent background, instead of in a right-hand margin. Defaults to FALSE.

title, x_lab, y_lab

Plot title and axis labels.

Value

A ggplot2::ggplot object.

Examples

ecdf_plot(lexical_decision, RT)

ecdf_plot(lexical_decision, RT, group = condition,
          reference_quantiles = c(0.25, 0.5, 0.75))