diff --git a/pyFTS/models/incremental/IncrementalEnsemble.py b/pyFTS/models/incremental/IncrementalEnsemble.py
index c4ea174..c494054 100644
--- a/pyFTS/models/incremental/IncrementalEnsemble.py
+++ b/pyFTS/models/incremental/IncrementalEnsemble.py
@@ -65,18 +65,20 @@ class IncrementalEnsembleFTS(ensemble.EnsembleFTS):
 
         ret = []
 
-        for k in np.arange(0, l):
+        for k in np.arange(self.max_lag, l):
 
-            data_window.append(data[k])
+            k2 = k - self.max_lag
 
-            if k >= self.window_length:
+            data_window.append(data[k2])
+
+            if k2 >= self.window_length:
                 data_window.pop(0)
 
-            if k % self.batch_size == 0 and k >= self.window_length:
+            if k % self.batch_size == 0 and k2 >= self.window_length:
                 self.train(data_window, **kwargs)
 
             if len(self.models) > 0:
-                sample = data[k: k + self.max_lag]
+                sample = data[k2: k]
                 tmp = self.get_models_forecasts(sample)
                 point = self.get_point(tmp)
                 ret.append(point)