diff --git a/src/model.py b/src/model.py
index 1c0e558..2c51fa4 100644
--- a/src/model.py
+++ b/src/model.py
@@ -81,7 +81,7 @@ def normalize_belief_for_uncertainty(self):
         
         # some floating-point issues, as usual with Python
         self.b = round(self.b, 4)
-        self.d = round(self.b, 4)
+        self.d = round(self.d, 4)
         
     def project(self):
         return b + a*u