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interplot (version 0.1.0.2)

interplot.lmerMod: Plot Conditional Coefficients in Mixed-Effects Models with Interaction Terms

Description

interplot.mlm is a method to calculate conditional coefficient estimates from the results of multilevel (mixed-effects) regression models with interaction terms.

Usage

## S3 method for class 'lmerMod':
interplot(m, var1, var2, plot = TRUE, point = FALSE,
  sims = 5000, xmin = NA, xmax = NA)

Arguments

m
A model object including an interaction term, or, alternately, a data frame recording conditional coefficients.
var1
The name (as a string) of the variable of interest in the interaction term; its conditional coefficient estimates will be plotted.
var2
The name (as a string) of the other variable in the interaction term.
plot
A logical value indicating whether the output is a plot or a dataframe including the conditional coefficient estimates of var1, their upper and lower bounds, and the corresponding values of var2.
point
A logical value determining the format of plot. By default, the function produces a line plot when var2 takes on ten or more distinct values and a point (dot-and-whisker) plot otherwise; option TRUE forces a point plot.
sims
Number of independent simulation draws used to calculate upper and lower bounds of coefficient estimates: lower values run faster; higher values produce smoother curves.
xmin
A numerical value indicating the minimum value shown of x shown in the graph. Rarely used.
xmax
A numerical value indicating the maximum value shown of x shown in the graph. Rarely used.

Value

  • The function returns a ggplot object.

Details

interplot.mlm is a S3 method from the interplot. It works on mixed-effects objects with class lmerMod and glmerMod. Because the output function is based on ggplot, any additional arguments and layers supported by ggplot2 can be added with the +.