Whereas the direction of main effects can be interpreted from the sign of the estimate, the interpretation of interaction effects often requires plots. This task is facilitated by the R package sjPlot (Lüdecke, 2022). For instance, using the plot_model function, I plotted the interaction between two continuous variables.

library(lme4)
#> Loading required package: Matrix
library(sjPlot)
library(ggplot2) theme_set(theme_sjplot()) # Create data using code by Ben Bolker from # https://stackoverflow.com/a/