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rplotergm

ERGM MCMC diagnostics joint plot

How to combine MCMC diagnostic plots from two (or more) ERGM estimation in one figure as in the example below?

library(ergm)
library(latticeExtra)

data(florentine)

# Fit two ERGM models
model1 <- ergm(flomarriage ~ edges + kstar(2))
model2 <- ergm(flomarriage ~ edges + kstar(2) + triangle)

mcmc.diagnostic(model1)
mcmc.diagnostic(model2)

enter image description here

Solution

  • Obviously you can "glue" together the plots in some image-editting program. To do it in R you'll need to use coda (used by ergm internally anyway) and some lattice gymnastics, for example:

    p1 <- model1$sample |>
  coda::as.mcmc.list() |>
  ergm_plot.mcmc.list(main = "Model 1")

p2 <- model2$sample |>
  coda::as.mcmc.list() |>
  ergm_plot.mcmc.list(main = "Model 2")

plot(p1, split=c(1,1,2,1) )
plot(p2, split=c(2,1,2,1), newpage = FALSE)

    enter image description here