diff --git a/courses/machine_learning/deepdive2/introduction_to_tensorflow/labs/1_core_tensorflow.ipynb b/courses/machine_learning/deepdive2/introduction_to_tensorflow/labs/1_core_tensorflow.ipynb
index ff0bfe6bf3..aa8899c36d 100644
--- a/courses/machine_learning/deepdive2/introduction_to_tensorflow/labs/1_core_tensorflow.ipynb
+++ b/courses/machine_learning/deepdive2/introduction_to_tensorflow/labs/1_core_tensorflow.ipynb
@@ -452,7 +452,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "errors = (Y_hat - Y)**2\n",
+    "errors = (Y_hat - Y_test)**2\n",
     "loss = tf.reduce_mean(errors)\n",
     "loss.numpy()"
    ]