diff --git a/src/main/scala/com/databricks/spark/sql/perf/mllib/feature/QuantileDiscretizer.scala b/src/main/scala/com/databricks/spark/sql/perf/mllib/feature/QuantileDiscretizer.scala
index 47674f7..cf32b0f 100644
--- a/src/main/scala/com/databricks/spark/sql/perf/mllib/feature/QuantileDiscretizer.scala
+++ b/src/main/scala/com/databricks/spark/sql/perf/mllib/feature/QuantileDiscretizer.scala
@@ -31,6 +31,7 @@ object QuantileDiscretizer extends BenchmarkAlgorithm with TestFromTraining with
     import ctx.params._
     new ml.feature.QuantileDiscretizer()
       .setInputCol(inputCol)
+      .setOutputCol(outputCol)
       .setNumBuckets(bucketizerNumBuckets)
       .setRelativeError(relativeError)
   }
diff --git a/src/main/scala/com/databricks/spark/sql/perf/mllib/feature/UnaryTransformer.scala b/src/main/scala/com/databricks/spark/sql/perf/mllib/feature/UnaryTransformer.scala
index 8209bec..bd7b3cc 100644
--- a/src/main/scala/com/databricks/spark/sql/perf/mllib/feature/UnaryTransformer.scala
+++ b/src/main/scala/com/databricks/spark/sql/perf/mllib/feature/UnaryTransformer.scala
@@ -3,4 +3,5 @@ package com.databricks.spark.sql.perf.mllib.feature
 /** Trait defining common state/methods for featurizers taking a single input col */
 private[feature] trait UnaryTransformer {
   private[feature] val inputCol = "inputCol"
+  private[feature] val outputCol = "outputCol"
 }