1 files changed, 8 insertions, 1 deletions
diff --git a/tensorflow/contrib/boosted_trees/kernels/split_handler_ops.cc b/tensorflow/contrib/boosted_trees/kernels/split_handler_ops.cc
index 44a8ffaf4b..04e32267cc 100644
--- a/tensorflow/contrib/boosted_trees/kernels/split_handler_ops.cc
+++ b/tensorflow/contrib/boosted_trees/kernels/split_handler_ops.cc
@@ -422,6 +422,10 @@ class BuildSparseInequalitySplitsOp : public BaseBuildSplitOp {
               GradientStats(*gradients_t, *hessians_t, bucket_idx);
         }
         present_gradient_stats *= normalizer_ratio;
+        GradientStats not_present =
+            root_gradient_stats - present_gradient_stats;
+        // If there was (almost) no sparsity, fix the default direction to LEFT.
+        bool fixed_default_direction = not_present.IsAlmostZero();
 
         GradientStats left_gradient_stats;
         for (int64 element_idx = start_index; element_idx < end_index;
@@ -441,6 +445,7 @@ class BuildSparseInequalitySplitsOp : public BaseBuildSplitOp {
           // backward pass gradients.
           GradientStats right_gradient_stats =
               present_gradient_stats - left_gradient_stats;
+
           {
             NodeStats left_stats_default_left =
                 ComputeNodeStats(root_gradient_stats - right_gradient_stats);
@@ -457,7 +462,9 @@ class BuildSparseInequalitySplitsOp : public BaseBuildSplitOp {
               best_dimension_idx = dimension_id;
             }
           }
-          {
+          // Consider calculating the default direction only when there were
+          // enough missing examples.
+          if (!fixed_default_direction) {
             NodeStats left_stats_default_right =
                 ComputeNodeStats(left_gradient_stats);
             NodeStats right_stats_default_right =