diff --git a/hapi/metrics.py b/hapi/metrics.py
index 5f79b8f11d6427156e53d99581e21eea8a2aad94..056b983d7decc212ab3891f31da1b7197872bcd3 100644
--- a/hapi/metrics.py
+++ b/hapi/metrics.py
@@ -54,7 +54,7 @@ class Metric(object):
                        |                      ||
                     {model}                   ||
                        |                      ||
-                 outputs labels               ||
+                outputs & labels              ||
                        |                      ||    tensor data
              {Metric.add_metric_op}           ||
                        |                      ||