nice_qq: Easy QQ plots per group

In RemPsyc/rempsyc: Convenience Functions for Psychology

Easy QQ plots per group

Description

Easily make nice per-group QQ plots through a wrapper around the ggplot2 and qqplotr packages.

Usage

nice_qq(
  data,
  variable,
  group = NULL,
  colours,
  groups.labels = NULL,
  grid = TRUE,
  shapiro = FALSE,
  title = variable
)

Arguments

data	The data frame.
variable	The dependent variable to be plotted.
group	The group by which to plot the variable.
colours	Desired colours for the plot, if desired.
groups.labels	How to label the groups.
grid	Logical, whether to keep the default background grid or not. APA style suggests not using a grid in the background, though in this case some may find it useful to more easily estimate the slopes of the different groups.
shapiro	Logical, whether to include the p-value from the Shapiro-Wilk test on the plot.
title	An optional title, if desired.

Value

A qq plot of class ggplot, by group (if provided), along a reference interpretation helper, the 95% confidence band.

See Also

Other functions useful in assumption testing: nice_assumptions, nice_density, nice_normality, nice_var, nice_varplot. Tutorial: https://rempsyc.remi-theriault.com/articles/assumptions

Examples

# Make the basic plot
nice_qq(
  data = iris,
  variable = "Sepal.Length",
  group = "Species"
)

# Further customization
nice_qq(
  data = iris,
  variable = "Sepal.Length",
  group = "Species",
  colours = c("#00BA38", "#619CFF", "#F8766D"),
  groups.labels = c("(a) Setosa", "(b) Versicolor", "(c) Virginica"),
  grid = FALSE,
  shapiro = TRUE,
  title = NULL
)

RemPsyc/rempsyc documentation built on July 2, 2024, 9:41 p.m.