diff --git a/code/bolsonaro/trainer.py b/code/bolsonaro/trainer.py
index e5ca49b4bef86a4386f314801d9c36ec8ea2fa7f..01d0a036c8058cb55f947c0d80645b5619da0cdb 100644
--- a/code/bolsonaro/trainer.py
+++ b/code/bolsonaro/trainer.py
@@ -25,9 +25,9 @@ class Trainer(object):
             self._logger.debug('Fitting the forest on train subset and OMP on dev subset.')
         else:
             X_forest = np.concatenate([self._dataset.X_train, self._dataset.X_dev])
-            X_omp = np.concatenate([self._dataset.X_train, self._dataset.X_dev])
+            X_omp = X_forest
             y_forest = np.concatenate([self._dataset.y_train, self._dataset.y_dev])
-            y_omp = np.concatenate([self._dataset.y_train, self._dataset.y_dev])
+            y_omp = y_forest
             self._logger.debug('Fitting both the forest and OMP on train+dev subsets.')
 
         model.fit(