diff --git a/src/twomartens/masterthesis/evaluate.py b/src/twomartens/masterthesis/evaluate.py
index 1920c7d..6b45b7c 100644
--- a/src/twomartens/masterthesis/evaluate.py
+++ b/src/twomartens/masterthesis/evaluate.py
@@ -382,4 +382,6 @@ def get_mean_average_precision(average_precisions: List[float]) -> float:
     Returns:
         mean average precision over all classes
     """
-    return np.average(average_precisions[1:])
+    average_precisions = np.copy(average_precisions)
+    average_precisions = average_precisions[average_precisions != 0.0]
+    return np.average(average_precisions[:])