ggsmatr-vignette

This vignette shows how to create a scatter plot based on the coefficients from (Standardised) Major Axis Estimation fit using the “smatr” package and “ggplot” in R.

Load packages

library(ggsmatr)
library(smatr)
library(ggplot2)
#> Warning: package 'ggplot2' was built under R version 4.1.3

Fit a SMA using smatr package:

data(iris)
fit <- sma(Petal.Width ~ Petal.Length+ Species, data=iris)

We want to plot the results using ggplot package:

# plot
ggsmatr(data =  iris, groups = "Species", xvar =  "Petal.Length", yvar =
          "Petal.Width", sma.fit =  fit)
#>        group    r2  pval
#> 1     setosa 0.110 0.019
#> 2 versicolor 0.619 0.000
#> 3  virginica 0.104 0.023

If we want to change the axis labels, label position and colors we can use the default arguments implemented in ggplot:

#Plot is saved as ggp object, and can be edited using ggplot parameters.
library(ggplot2)
ggp + xlab("x axis name") + ylab("y axis name") +theme(legend.position = "right",
legend.title=element_blank()) + scale_colour_manual(values = c("black", "firebrick", "cornflowerblue"))