gistfile1.txt

library(rstanarm)
library(tidybayes)
m1 <- stan_lmer(t2_accuracy ~ lag*condition + (1|p), data = rsvp_accuracy)

nd <- expand.grid(condition=unique(rsvp_accuracy$condition), lag=factor(c(1,3))) %>% as.tibble() %>% mutate(p=Inf)

m1.preds <- add_fitted_samples(nd, m1)
m1.preds.wide <- m1.preds %>% 
  data.table::dcast(.iteration+condition~lag) 

m1.preds.wide %>% 
  mutate(d=`1`-`3`) %>% 
  data.table::dcast(.iteration~condition, value.var="d") %>% 
  transmute(fam-omm, fam-control, control-omm) %>% 
  data.table::melt() %>% 
  group_by(variable) %>% 
  mean_qi()