diff --git a/02-Discrete-Bayes.ipynb b/02-Discrete-Bayes.ipynb
index 2073635..7e0702e 100644
--- a/02-Discrete-Bayes.ipynb
+++ b/02-Discrete-Bayes.ipynb
@@ -1667,7 +1667,7 @@
    "source": [
     "## Adding Uncertainty to the Prediction\n",
     "\n",
-    "`perfect_sensor()` assumes perfect measurements, but all sensors have noise. What if the sensor reported that our dog moved one space, but he actually moved two spaces, or zero? This may sound like an insurmountable problem, but let's model it and see what happens.\n",
+    "`perfect_predict()` assumes perfect measurements, but all sensors have noise. What if the sensor reported that our dog moved one space, but he actually moved two spaces, or zero? This may sound like an insurmountable problem, but let's model it and see what happens.\n",
     "\n",
     "Assume that the sensor's movement measurement is 80% likely to be correct, 10% likely to overshoot one position to the right, and 10% likely to undershoot to the left. That is, if the movement measurement is 4 (meaning 4 spaces to the right), the dog is 80% likely to have moved 4 spaces to the right, 10% to have moved 3 spaces, and 10% to have moved 5 spaces.\n",
     "\n",