diff --git a/matlab/global_initialization.m b/matlab/global_initialization.m
index a7781e84d99c24b9053415e1c258a781b551c54f..397951b68b5b624e14f917dcd6cd9864dfb76a73 100644
--- a/matlab/global_initialization.m
+++ b/matlab/global_initialization.m
@@ -454,6 +454,7 @@ simplex.tolerance.f = 1e-4;
 simplex.maxiter = 5000;
 simplex.maxfcallfactor = 500;
 simplex.maxfcall = [];
+simplex.delta_factor=0.05;
 options_.simplex = simplex;
 
 % CMAES optimization routine.