intplot: Interaction Plots with Error Bars

In greenwood-stat/catstats: Statistics for Montana State University Bobcats

Interaction Plots with Error Bars

Description

This function allows you to generate interaction plots for a Two-Way ANOVA with error bars.

Usage

intplot(
  formula = NULL,
  data = NULL,
  type = "b",
  x.cont = FALSE,
  legend = TRUE,
  trace.label = NULL,
  leg.lab = NULL,
  fixed = FALSE,
  x.leg = NULL,
  y.leg = NULL,
  cex.leg = 1,
  ncol = 1,
  pch = c(16, 21, 15, 22, 17, 24, c(3:14)),
  fun = function(x) mean(x, na.rm = TRUE),
  ci.fun = function(x) c(fun(x) - se(x), fun(x) + se(x)),
  err.width = if (length(levels(as.factor(x.factor))) > 10) 0 else 0.1,
  err.col = col,
  err.lty = 1,
  xlim = NULL,
  ylim = NULL,
  cex = NULL,
  lwd = NULL,
  col = 1:10,
  cex.axis = 1,
  xaxt = "s",
  main = NULL,
  cld = F,
  cldshift = 0.1,
  cldcol = "white",
  hor.shift = 0.02,
  ...
)

Arguments

formula	an object of class "formula" (or one that can be coerced to that class); a symbolic description of the model to be plotted. The details of the model specification are given under "Details".
data	a required data frame containing the variables for the plot.
type	character. One of "p" or "b". Defaults to "b" for base version that adds lines between points. Choose "p" to not have lines (just points with error bars).
x.cont	boolean. Defaults to FALSE as current interaction plots are not for continuous predictors but included for future development.
legend	boolean. Defaults to TRUE. Adds legend to plot, removal causes other changes.
trace.label	text. Adds a text label to the legend
leg.lab	text. Changes the names of levels used in legend, must match the number of levels.
fixed	boolean. Defaults to FALSE and relates to order of labels in legend.
x.leg	Defaults to NULL. Determines x-location of legend on plot.
y.leg	Defaults to NULL. Determines x-location of legend on plot.
cex.leg	Defaults to 1. Size of text in legend.
ncol	Defaults to 1. Number of columns for the legend. 1 is usually best.
pch	Symbols for means in plot. Match number of levels as used in first variable in formula.
fun	Function for finding the point estimates, defaults to finding the mean. Change not recommended.
ci.fun	Function for finding the width of error bars, with default of plus/minus 1 SE. See function for details to change this.
err.width	Defaults to 0.1 if less than 10 levels and 0 otherwise. Can specify wider or smaller than 0.1.
err.col	Defaults to matching order of levels and other aspects of plot but can make contrasting error bars with other choices.
err.lty	Defaults to 1. Line type for the error bars. Best to leave solid but can be changed.
xlim	Defaults to NULL. Can make other choices to modify default choice that tries to make room for standard versions of interaction plots.
ylim	Defaults to NULL. Can make other choices to modify default choice that tries to make room for standard versions of interaction plots.
cex	Defaults to 1. Size of points for means in plot.
lwd	Deafults to 1. Line width for lines in plot.
col	Defaults to 1:10 for the colors used in the plot.
cex.axis	Defaults to 1. Size of text for tick marks on x and y axis.
xaxt	Defaults to "s". Change to "n" to remove x-axis tick marks.
main	Title for plot.
cld	boolean. Defaults to FALSE. If true, adds compact letter display from Tukey's HSD that is run.
cldshift	Defaults to 0.1. Amount to shift letters added to plot.
cldcol	Colors for letters for CLD.
...	optional arguments to be passed to plot.

Details

Function for making nice looking interaction plots with 1 SE-based intervals. Add Tukey's HSD results via Compact Letter Displays.

Examples

# must have the carData package installed
data(TitanicSurvival, package = "carData")
intplot(age ~ sex * survived, data = TitanicSurvival)

greenwood-stat/catstats documentation built on Dec. 14, 2024, 6:25 p.m.