I am working on graphing the predicted values from a multilevel model (using the lme4 package). I am able to do this successfully using the Effect() function. As shown below:
library(lme4)
library(effects)
m1=lmer(price~depth*cut+(1|cut),diamonds)
plot(Effect(c("cut","depth"),m1))
But, I want to present these same data as a single plot with a legend. Using ggplots, I can do this; but, I lose the error bars, as shown below:
ggplot(data.frame(Effect(c("cut","depth"),m1)),
aes(x=depth,y=fit,color=cut,group=cut))+
geom_line()
How can I recreate the first plot (with error bars) as a single plot?


