diff --git a/01_intro/powersim-intro.pdf b/01_intro/powersim-intro.pdf
index aa02ee4..ea078be 100644
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diff --git a/02_ttest/powersim-ttest.R b/02_ttest/powersim-ttest.R
index 8344d51..a608531 100644
--- a/02_ttest/powersim-ttest.R
+++ b/02_ttest/powersim-ttest.R
@@ -31,7 +31,7 @@
 #' 
 #' Hypothesis
 #' 
-#' - H$_0\colon~ \mu_x - \mu_y = \delta = 0$
+#' - $H_0\colon~ \mu_x - \mu_y = \delta = 0$
 #'
 
 #' ## Power simulation
diff --git a/02_ttest/powersim-ttest.md b/02_ttest/powersim-ttest.md
index de3c29c..69f92a1 100644
--- a/02_ttest/powersim-ttest.md
+++ b/02_ttest/powersim-ttest.md
@@ -25,7 +25,7 @@ Assumptions
 
 Hypothesis
 
-- H$_0\colon~ \mu_x - \mu_y = \delta = 0$
+- $H_0\colon~ \mu_x - \mu_y = \delta = 0$
 
 ## Power simulation
 
diff --git a/04_ancova/intro-ancova.pdf b/04_ancova/intro-ancova.pdf
index 79d02d4..bb6b83e 100644
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diff --git a/05_mixed1/intro-lmm.pdf b/05_mixed1/intro-lmm.pdf
index c5a791a..a2c0cca 100644
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diff --git a/06_mixed2/intro-datsimlmm.pdf b/06_mixed2/intro-datsimlmm.pdf
index 99aaa78..ba0a78b 100644
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