uncertainty/deep-ppl.md

@@ -12,7 +12,7 @@ As illustrated below the user specified probabilistic program specifies how to g
 
 **How to Set-up a PPL Program**
 
-The goal is to infer a probabilistic model θ for observed data x_1, ..., x_n: p(θ|x_1, ..., x_n).
+The goal is to infer a probabilistic model θ for observed data x<sup>1</sup>, ..., x_n: p(θ|x_1, ..., x_n).
 
 **Conceptual Categorisation of Deep Probabilistic Programming Languages (PPL)**