Plot.brmsfit creates empty plot when model contains multiple predictors

I am new to brms and bayesian analysis. I am trying to run a mixed model with two (fixed effects) predictors e.g. A ~ 1+ B + C + (1|ID) - it seems to run and produces a summary, conditional effects plot, and hypothesis estimates, however I am concerned that it does not create a plot when I run plot.brmsfit, while for a single predictor e.g. A~ 1+ B+ (1|ID) it does.

I am not sure if this is expected behaviour or if it indicates I am doing something wrong.

I have tried to create a minimal reproducible example using the Iris dataset; this gives a warning that ‘parts of the model do not converge’ which is not the case in my dataset, but does reproduce the issue with plot.brmsfit - hopefully this is enough to demonstrate my query.

install.packages("brms",repos = "")
iris$ID <- c(1:150)

#single predictor
m <- brm(Sepal.Length ~ 1 + Petal.Length  + (1|ID), data=iris, iter=10000)
#plot.brmsfit produces expected output
#as do other functions
hypothesis(m, "Petal.Length>0")

#additional predictor
m <- brm(Sepal.Length ~ 1 + Petal.Length + Sepal.Width + (1|ID), data=iris, iter=10000)
#plot.brmsfit now creates empty plot
#other functions still behave as expected
hypothesis(m, "Petal.Length>0")
  • Operating System: macOS Mojave 10.14.6
  • brms Version: 2.12.0


The plot methods produces expected results when I run it on my machine. I have seen this happening from time to time within Rstudio. Usually, running the plot again should fix it. Due to the complexity of the plot for 20k draws, creating the plot may take a little longer.

Thanks @paul.buerkner - you were right, looks like it just needed more time to run!