diff --git a/predtuner/modeledapp.py b/predtuner/modeledapp.py
index fa30d8e7ddd831c3fabc728867f06ca024f03cac..a188eb9ad0c9ecc0fd4f66920fb5d15540dc1fd4 100644
--- a/predtuner/modeledapp.py
+++ b/predtuner/modeledapp.py
@@ -460,6 +460,8 @@ class ApproxModeledTuner(ApproxTuner):
             def qos_speedup(conf):
                 return conf.validated_qos if validated else conf.qos, conf.speedup
 
+            if not confs:
+                return np.zeros((2, 0))
             sorted_points = np.array(
                 sorted([qos_speedup(c) for c in confs], key=lambda p: p[0])
             ).T