diff --git a/dlib/svm/structural_svm_graph_labeling_problem.h b/dlib/svm/structural_svm_graph_labeling_problem.h
index 79b490e97..9c0cf4c8a 100644
--- a/dlib/svm/structural_svm_graph_labeling_problem.h
+++ b/dlib/svm/structural_svm_graph_labeling_problem.h
@@ -199,7 +199,7 @@ namespace dlib
                     << "\n\t loss: " << loss 
                     << "\n\t this: " << this );
 
-            loss_pos = loss;
+            loss_neg = loss;
         }
 
         double get_loss_on_negative_class (