I have a bar plot with 3 bars representing a categorical variable across a grouping variable.
I wish to add significance bar for pairwise comparison between the 3 groups
here is my code and error(a is the plot)
a+geom_signif(comparisons = list(c("1990-1999", "2000-2009"), c("2000-2009", "2010-2020")), y_position = c(1.1,1.1), tip_length = c(0.001,0.001,0.001,0.001),
xmin = c(1,2.1), xmax = c(1.9,3))
Error in f(...) : Set either the xmin, xmax values or the comparisons
without the last line it works nicely, however I wish to change the width of the significance bars