diff --git a/Running Start/CSB320 - Machine Learning Concepts/Class 6-4 (Reinforcement Learning).md b/Running Start/CSB320 - Machine Learning Concepts/Class 6-4 (Reinforcement Learning).md
index 1c5028e..81c4a3f 100644
--- a/Running Start/CSB320 - Machine Learning Concepts/Class 6-4 (Reinforcement Learning).md	
+++ b/Running Start/CSB320 - Machine Learning Concepts/Class 6-4 (Reinforcement Learning).md	
@@ -12,4 +12,6 @@
 	- $\varepsilon$-greedy strategy
 		- with probability $\varepsilon$ take a random action, with probability $1-\varepsilon$ take the best known actions
 		- $\varepsilon$ often starts high and decreases over time
+	- $\rho$ (regret) can be used to find how good a strategy is
+		- this is the difference between how much reward was gotten and the maximum reward possible if distributions are known ahead of time
 	- 
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