diff --git a/vignettes/continuous.Rmd b/vignettes/continuous.Rmd
index e332a055..8e6c52af 100644
--- a/vignettes/continuous.Rmd
+++ b/vignettes/continuous.Rmd
@@ -205,10 +205,10 @@ in the __loo__ package:
 
 ```{r, continuous-kidiq-loo}
 # Compare them with loo
-loo1 <- loo(post1, cores = 2)
-loo2 <- loo(post2, cores = 2)
-loo3 <- loo(post3, cores = 2)
-loo4 <- loo(post4, cores = 2)
+loo1 <- loo(post1, cores = 1)
+loo2 <- loo(post2, cores = 1)
+loo3 <- loo(post3, cores = 1)
+loo4 <- loo(post4, cores = 1)
 (comp <- loo_compare(loo1, loo2, loo3, loo4))
 ```
 
diff --git a/vignettes/count.Rmd b/vignettes/count.Rmd
index 283de9df..3a54cfcc 100644
--- a/vignettes/count.Rmd
+++ b/vignettes/count.Rmd
@@ -223,8 +223,8 @@ When we comparing the models using the __loo__ package we also see a clear
 preference for the negative binomial model
 
 ```{r, count-roaches-loo}
-loo1 <- loo(stan_glm1, cores = 2)
-loo2 <- loo(stan_glm2, cores = 2)
+loo1 <- loo(stan_glm1, cores = 1)
+loo2 <- loo(stan_glm2, cores = 1)
 loo_compare(loo1, loo2)
 ```