feat: Synthetic difference in differences

core/src/main/python/synapse/ml/causal/DiffInDiffModel.py

@@ -0,0 +1,50 @@
+# Copyright (C) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License. See LICENSE in project root for information.
+
+import sys
+
+if sys.version >= "3":
+    basestring = str
+
+from synapse.ml.causal._DiffInDiffModel import _DiffInDiffModel
+from pyspark.ml.common import inherit_doc
+from pyspark.sql import SparkSession, DataFrame
+from pyspark import SparkContext, SQLContext
+
+
+@inherit_doc
+class DiffInDiffModel(_DiffInDiffModel):
+    @staticmethod
+    def _mapOption(option, func):
+        return func(option.get()) if option.isDefined() else None
+
+    @staticmethod
+    def _unwrapOption(option):
+        return DiffInDiffModel._mapOption(option, lambda x: x)
+
+    def __init__(self, java_obj=None) -> None:
+        super(DiffInDiffModel, self).__init__(java_obj=java_obj)
+
+        ctx = SparkContext._active_spark_context
+        sql_ctx = SQLContext.getOrCreate(ctx)
+
+        self.summary = java_obj.getSummary()
+        self.treatmentEffect = self.summary.treatmentEffect()
+        self.standardError = self.summary.standardError()
+        self.timeIntercept = DiffInDiffModel._unwrapOption(self.summary.timeIntercept())
+        self.unitIntercept = DiffInDiffModel._unwrapOption(self.summary.unitIntercept())
+        self.timeWeights = DiffInDiffModel._mapOption(
+            java_obj.getTimeWeights(), lambda x: DataFrame(x, sql_ctx)
+        )
+        self.unitWeights = DiffInDiffModel._mapOption(
+            java_obj.getUnitWeights(), lambda x: DataFrame(x, sql_ctx)
+        )
+        self.timeRMSE = DiffInDiffModel._unwrapOption(self.summary.timeRMSE())
+        self.unitRMSE = DiffInDiffModel._unwrapOption(self.summary.unitRMSE())
+        self.zeta = DiffInDiffModel._unwrapOption(self.summary.zeta())
+        self.lossHistoryTimeWeights = DiffInDiffModel._unwrapOption(
+            self.summary.getLossHistoryTimeWeightsJava()
+        )
+        self.lossHistoryUnitWeights = DiffInDiffModel._unwrapOption(
+            self.summary.getLossHistoryUnitWeightsJava()
+        )

core/src/main/scala/com/microsoft/azure/synapse/ml/causal/BaseDiffInDiffEstimator.scala

@@ -0,0 +1,183 @@
+// Copyright (C) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License. See LICENSE in project root for information.
+
+package com.microsoft.azure.synapse.ml.causal
+
+import com.microsoft.azure.synapse.ml.causal.linalg.DVector
+import com.microsoft.azure.synapse.ml.codegen.Wrappable
+import com.microsoft.azure.synapse.ml.core.schema.DatasetExtensions
+import com.microsoft.azure.synapse.ml.logging.{FeatureNames, SynapseMLLogging}
+import com.microsoft.azure.synapse.ml.param.DataFrameParam
+import org.apache.spark.SparkException
+import org.apache.spark.ml.feature.VectorAssembler
+import org.apache.spark.ml.param.{Param, ParamMap, Params}
+import org.apache.spark.ml.regression.LinearRegression
+import org.apache.spark.ml.util.Identifiable
+import org.apache.spark.ml.{ComplexParamsReadable, ComplexParamsWritable, Estimator, Model}
+import org.apache.spark.sql.types.{BooleanType, NumericType, StructField, StructType}
+import org.apache.spark.sql.{DataFrame, Dataset}
+
+import java.util
+
+abstract class BaseDiffInDiffEstimator(override val uid: String)
+  extends Estimator[DiffInDiffModel]
+    with DiffInDiffEstimatorParams {
+
+  private def validateFieldNumericOrBooleanType(field: StructField): Unit = {
+    val dataType = field.dataType
+    require(dataType.isInstanceOf[NumericType] || dataType == BooleanType,
+      s"Column ${field.name} must be numeric type or boolean type, but got $dataType instead.")
+  }
+
+  protected def validateFieldNumericType(field: StructField): Unit = {
+    val dataType = field.dataType
+    require(dataType.isInstanceOf[NumericType],
+      s"Column ${field.name} must be numeric type, but got $dataType instead.")
+  }
+
+  override def transformSchema(schema: StructType): StructType = {
+    validateFieldNumericOrBooleanType(schema(getPostTreatmentCol))
+    validateFieldNumericOrBooleanType(schema(getTreatmentCol))
+    validateFieldNumericType(schema(getOutcomeCol))
+    schema
+  }
+
+  override def copy(extra: ParamMap): Estimator[DiffInDiffModel] = defaultCopy(extra)
+
+  private[causal] val findInteractionCol = DatasetExtensions.findUnusedColumnName("interaction") _
+
+  private[causal] def fitLinearModel(df: DataFrame,
+                                     featureCols: Array[String],
+                                     fitIntercept: Boolean,
+                                     weightCol: Option[String] = None) = {
+
+    val featuresCol = DatasetExtensions.findUnusedColumnName("features", df)
+    val assembler = new VectorAssembler()
+      .setInputCols(featureCols)
+      .setOutputCol(featuresCol)
+
+    val regression = weightCol
+      .map(new LinearRegression().setWeightCol)
+      .getOrElse(new LinearRegression())
+
+    regression
+      .setFeaturesCol(featuresCol)
+      .setLabelCol(getOutcomeCol)
+      .setFitIntercept(fitIntercept)
+      .setLoss("squaredError")
+      .setRegParam(1E-10)
+
+    assembler.transform _ andThen regression.fit apply df
+  }
+}
+
+case class DiffInDiffSummary(treatmentEffect: Double, standardError: Double,
+                             timeWeights: Option[DVector] = None,
+                             timeIntercept: Option[Double] = None,
+                             timeRMSE: Option[Double] = None,
+                             unitWeights: Option[DVector] = None,
+                             unitIntercept: Option[Double] = None,
+                             unitRMSE: Option[Double] = None,
+                             zeta: Option[Double] = None,
+                             lossHistoryTimeWeights: Option[List[Double]] = None,
+                             lossHistoryUnitWeights: Option[List[Double]] = None) {
+  import scala.collection.JavaConverters._
+
+  def getLossHistoryTimeWeightsJava: Option[util.List[Double]] = {
+    lossHistoryTimeWeights.map(_.asJava)
+  }
+
+  def getLossHistoryUnitWeightsJava: Option[util.List[Double]] = {
+    lossHistoryUnitWeights.map(_.asJava)
+  }
+}
+
+class DiffInDiffModel(override val uid: String)
+  extends Model[DiffInDiffModel]
+    with HasUnitCol
+    with HasTimeCol
+    with Wrappable
+    with ComplexParamsWritable
+    with SynapseMLLogging {
+
+  logClass(FeatureNames.Causal)
+
+  final val timeIndex = new DataFrameParam(this, "timeIndex", "time index")
+  def getTimeIndex: DataFrame = $(timeIndex)
+  def setTimeIndex(value: DataFrame): this.type = set(timeIndex, value)
+
+  final val timeIndexCol = new Param[String](this, "timeIndexCol", "time index column")
+  def getTimeIndexCol: String = $(timeIndexCol)
+  def setTimeIndexCol(value: String): this.type = set(timeIndexCol, value)
+
+  final val unitIndex = new DataFrameParam(this, "unitIndex", "unit index")
+  def getUnitIndex: DataFrame = $(unitIndex)
+  def setUnitIndex(value: DataFrame): this.type = set(unitIndex, value)
+
+  final val unitIndexCol = new Param[String](this, "unitIndexCol", "unit index column")
+  def getUnitIndexCol: String = $(unitIndexCol)
+  def setUnitIndexCol(value: String): this.type = set(unitIndexCol, value)
+
+  override protected lazy val pyInternalWrapper = true
+
+  def this() = this(Identifiable.randomUID("DiffInDiffModel"))
+
+  private final var summary: Option[DiffInDiffSummary] = None
+
+  def getSummary: DiffInDiffSummary = summary.getOrElse {
+    throw new SparkException(
+      s"No summary available for this ${this.getClass.getSimpleName}")
+  }
+
+  private[causal] def setSummary(summary: Option[DiffInDiffSummary]): this.type = {
+    this.summary = summary
+    this
+  }
+
+  override def copy(extra: ParamMap): DiffInDiffModel = {
+    copyValues(new DiffInDiffModel(uid), extra)
+      .setSummary(this.summary)
+      .setParent(parent)
+  }
+
+  override def transform(dataset: Dataset[_]): DataFrame = dataset.toDF
+
+  override def transformSchema(schema: StructType): StructType = schema
+
+  def getTimeWeights: Option[DataFrame] = {
+    (get(timeIndex), getSummary.timeWeights) match {
+      case (Some(idxDf), Some(timeWeights)) =>
+        Some(
+          idxDf.join(timeWeights, idxDf(getTimeIndexCol) === timeWeights("i"), "left_outer")
+            .select(
+              idxDf(getTimeCol),
+              timeWeights("value")
+            )
+        )
+      case _ =>
+        None
+    }
+  }
+
+  def getUnitWeights: Option[DataFrame] = {
+    (get(unitIndex), getSummary.unitWeights) match {
+      case (Some(idxDf), Some(unitWeights)) =>
+        Some(
+          idxDf.join(unitWeights, idxDf(getUnitIndexCol) === unitWeights("i"), "left_outer")
+            .select(
+              idxDf(getUnitCol),
+              unitWeights("value")
+            )
+        )
+      case _ =>
+        None
+    }
+  }
+}
+
+object DiffInDiffModel extends ComplexParamsReadable[DiffInDiffModel]
+
+trait DiffInDiffEstimatorParams extends Params
+  with HasTreatmentCol
+  with HasOutcomeCol
+  with HasPostTreatmentCol

core/src/main/scala/com/microsoft/azure/synapse/ml/causal/CacheOps.scala

@@ -0,0 +1,21 @@
+// Copyright (C) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License. See LICENSE in project root for information.
+
+package com.microsoft.azure.synapse.ml.causal
+
+import breeze.linalg.{DenseVector => BDV}
+import com.microsoft.azure.synapse.ml.causal.linalg.DVector
+trait CacheOps[T] {
+  def checkpoint(data: T): T = data
+  def cache(data: T): T = data
+}
+
+object BDVCacheOps extends CacheOps[BDV[Double]] {
+  override def checkpoint(data: BDV[Double]): BDV[Double] = data
+  override def cache(data: BDV[Double]): BDV[Double] = data
+}
+
+object DVectorCacheOps extends CacheOps[DVector] {
+  override def checkpoint(data: DVector): DVector = data.localCheckpoint(true)
+  override def cache(data: DVector): DVector = data.cache
+}

core/src/main/scala/com/microsoft/azure/synapse/ml/causal/DiffInDiffEstimator.scala

@@ -0,0 +1,54 @@
+// Copyright (C) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License. See LICENSE in project root for information.
+
+package com.microsoft.azure.synapse.ml.causal
+
+import com.microsoft.azure.synapse.ml.codegen.Wrappable
+import com.microsoft.azure.synapse.ml.core.schema.DatasetExtensions
+import com.microsoft.azure.synapse.ml.logging.{FeatureNames, SynapseMLLogging}
+import org.apache.spark.ml.util.Identifiable
+import org.apache.spark.ml.{ComplexParamsReadable, ComplexParamsWritable}
+import org.apache.spark.sql._
+import org.apache.spark.sql.functions.col
+import org.apache.spark.sql.types._
+
+class DiffInDiffEstimator(override val uid: String)
+  extends BaseDiffInDiffEstimator(uid)
+    with ComplexParamsWritable
+    with Wrappable
+    with SynapseMLLogging {
+
+  logClass(FeatureNames.Causal)
+
+  def this() = this(Identifiable.randomUID("DiffInDiffEstimator"))
+
+  override def fit(dataset: Dataset[_]): DiffInDiffModel = logFit({
+    val interactionCol = findInteractionCol(dataset.columns.toSet)
+    val postTreatment = col(getPostTreatmentCol)
+    val treatment = col(getTreatmentCol)
+    val outcome = col(getOutcomeCol)
+
+    val didData = dataset.select(
+        postTreatment.cast(IntegerType).as(getPostTreatmentCol),
+        treatment.cast(IntegerType).as(getTreatmentCol),
+        outcome.cast(DoubleType).as(getOutcomeCol)
+      )
+      .withColumn(interactionCol, treatment * postTreatment)
+
+    val linearModel = fitLinearModel(
+      didData,
+      Array(getPostTreatmentCol, getTreatmentCol, interactionCol),
+      fitIntercept = true
+    )
+
+    val treatmentEffect = linearModel.coefficients(2)
+    val standardError = linearModel.summary.coefficientStandardErrors(2)
+    val summary = DiffInDiffSummary(treatmentEffect, standardError)
+
+    copyValues(new DiffInDiffModel(this.uid))
+      .setSummary(Some(summary))
+      .setParent(this)
+  }, dataset.columns.length)
+}
+
+object DiffInDiffEstimator extends ComplexParamsReadable[DiffInDiffEstimator]

core/src/main/scala/com/microsoft/azure/synapse/ml/causal/DoubleMLParams.scala

@@ -3,38 +3,14 @@
 
 package com.microsoft.azure.synapse.ml.causal
 
-import com.microsoft.azure.synapse.ml.core.contracts.{HasFeaturesCol, HasLabelCol, HasWeightCol}
+import com.microsoft.azure.synapse.ml.core.contracts.{HasFeaturesCol, HasWeightCol}
 import com.microsoft.azure.synapse.ml.param.EstimatorParam
-import org.apache.spark.ml.classification.{LogisticRegression, ProbabilisticClassifier}
-import org.apache.spark.ml.{Estimator, Model}
 import org.apache.spark.ml.ParamInjections.HasParallelismInjected
-import org.apache.spark.ml.param.shared.{HasMaxIter, HasPredictionCol}
-import org.apache.spark.ml.param.{DoubleArrayParam, DoubleParam, Param, Params}
+import org.apache.spark.ml.classification.{LogisticRegression, ProbabilisticClassifier}
+import org.apache.spark.ml.param.shared.HasMaxIter
+import org.apache.spark.ml.param.{DoubleArrayParam, DoubleParam, Params}
 import org.apache.spark.ml.regression.Regressor
-
-trait HasTreatmentCol extends Params {
-  val treatmentCol = new Param[String](this, "treatmentCol", "treatment column")
-  def getTreatmentCol: String = $(treatmentCol)
-
-  /**
-   * Set name of the column which will be used as treatment
-   *
-   * @group setParam
-   */
-  def setTreatmentCol(value: String): this.type = set(treatmentCol, value)
-}
-
-trait HasOutcomeCol extends Params {
-  val outcomeCol: Param[String] = new Param[String](this, "outcomeCol", "outcome column")
-  def getOutcomeCol: String = $(outcomeCol)
-
-  /**
-   * Set name of the column which will be used as outcome
-   *
-   * @group setParam
-   */
-  def setOutcomeCol(value: String): this.type = set(outcomeCol, value)
-}
+import org.apache.spark.ml.{Estimator, Model}
 
 trait DoubleMLParams extends Params
   with HasTreatmentCol with HasOutcomeCol with HasFeaturesCol
@@ -86,7 +62,7 @@ trait DoubleMLParams extends Params
   def setSampleSplitRatio(value: Array[Double]): this.type = set(sampleSplitRatio, value)
 
   private[causal] object DoubleMLModelTypes extends Enumeration {
-    type TreatmentType = Value
+    type DoubleMLModelTypes = Value
     val Binary, Continuous = Value
   }