diff --git a/src/twomartens/masterthesis/ssd.py b/src/twomartens/masterthesis/ssd.py
index 84c6baf..9fc698c 100644
--- a/src/twomartens/masterthesis/ssd.py
+++ b/src/twomartens/masterthesis/ssd.py
@@ -272,8 +272,7 @@ def _get_observations(detections: Sequence[Sequence[np.ndarray]]) -> List[List[n
         detections_image = np.asarray(detections[i])
         class_ids = np.argmax(detections_image[:, :-12],
                               axis=-1)
-        class_preds = detections_image[:, 0]
-        print(class_preds)
+        print(np.nonzero(class_ids[:]))
         detections_image = detections_image[np.nonzero(class_ids[:])]
         print(detections_image.shape)
         overlaps = bounding_box_utils.iou(detections_image[:, -12:-8],