Index: stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Classification/ClassificationProblemData.cs
===================================================================
--- stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Classification/ClassificationProblemData.cs	(revision 11157)
+++ stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Classification/ClassificationProblemData.cs	(revision 11158)
@@ -300,6 +300,6 @@
     }
 
-    public ClassificationProblemData(Dataset dataset, IEnumerable<string> allowedInputVariables, string targetVariable, IEnumerable<ITransformation> transformations = null)
-      : base(dataset, allowedInputVariables, transformations ?? Enumerable.Empty<ITransformation>()) {
+    public ClassificationProblemData(Dataset dataset, IEnumerable<string> allowedInputVariables, string targetVariable)
+      : base(dataset, allowedInputVariables) {
       var validTargetVariableValues = CheckVariablesForPossibleTargetVariables(dataset).Select(x => new StringValue(x).AsReadOnly()).ToList();
       var target = validTargetVariableValues.Where(x => x.Value == targetVariable).DefaultIfEmpty(validTargetVariableValues.First()).First();
Index: stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Clustering/ClusteringProblemData.cs
===================================================================
--- stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Clustering/ClusteringProblemData.cs	(revision 11157)
+++ stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Clustering/ClusteringProblemData.cs	(revision 11158)
@@ -21,5 +21,4 @@
 
 using System.Collections.Generic;
-using System.Linq;
 using HeuristicLab.Common;
 using HeuristicLab.Core;
@@ -87,6 +86,6 @@
     }
 
-    public ClusteringProblemData(Dataset dataset, IEnumerable<string> allowedInputVariables, IEnumerable<ITransformation> transformations = null)
-      : base(dataset, allowedInputVariables, transformations ?? Enumerable.Empty<ITransformation>()) {
+    public ClusteringProblemData(Dataset dataset, IEnumerable<string> allowedInputVariables)
+      : base(dataset, allowedInputVariables) {
     }
   }
Index: stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/DataAnalysisProblemData.cs
===================================================================
--- stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/DataAnalysisProblemData.cs	(revision 11157)
+++ stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/DataAnalysisProblemData.cs	(revision 11158)
@@ -38,5 +38,4 @@
     protected const string TrainingPartitionParameterName = "TrainingPartition";
     protected const string TestPartitionParameterName = "TestPartition";
-    protected const string TransformationsParameterName = "Transformations";
 
     #region parameter properites
@@ -52,7 +51,4 @@
     public IFixedValueParameter<IntRange> TestPartitionParameter {
       get { return (IFixedValueParameter<IntRange>)Parameters[TestPartitionParameterName]; }
-    }
-    public IFixedValueParameter<ReadOnlyItemList<ITransformation>> TransformationsParameter {
-      get { return (IFixedValueParameter<ReadOnlyItemList<ITransformation>>)Parameters[TransformationsParameterName]; }
     }
     #endregion
@@ -93,8 +89,4 @@
     }
 
-    public IEnumerable<ITransformation> Transformations {
-      get { return TransformationsParameter.Value; }
-    }
-
     public virtual bool IsTrainingSample(int index) {
       return index >= 0 && index < Dataset.Rows &&
@@ -119,12 +111,8 @@
     [StorableHook(HookType.AfterDeserialization)]
     private void AfterDeserialization() {
-      if (!Parameters.ContainsKey(TransformationsParameterName)) {
-        Parameters.Add(new FixedValueParameter<ReadOnlyItemList<ITransformation>>(TransformationsParameterName, "", new ItemList<ITransformation>().AsReadOnly()));
-        TransformationsParameter.Hidden = true;
-      }
       RegisterEventHandlers();
     }
 
-    protected DataAnalysisProblemData(Dataset dataset, IEnumerable<string> allowedInputVariables, IEnumerable<ITransformation> transformations = null) {
+    protected DataAnalysisProblemData(Dataset dataset, IEnumerable<string> allowedInputVariables) {
       if (dataset == null) throw new ArgumentNullException("The dataset must not be null.");
       if (allowedInputVariables == null) throw new ArgumentNullException("The allowedInputVariables must not be null.");
@@ -142,13 +130,8 @@
       int testPartitionEnd = dataset.Rows;
 
-      var transformationsList = new ItemList<ITransformation>(transformations ?? Enumerable.Empty<ITransformation>());
-
       Parameters.Add(new FixedValueParameter<Dataset>(DatasetParameterName, "", dataset));
       Parameters.Add(new FixedValueParameter<ReadOnlyCheckedItemList<StringValue>>(InputVariablesParameterName, "", inputVariables.AsReadOnly()));
       Parameters.Add(new FixedValueParameter<IntRange>(TrainingPartitionParameterName, "", new IntRange(trainingPartitionStart, trainingPartitionEnd)));
       Parameters.Add(new FixedValueParameter<IntRange>(TestPartitionParameterName, "", new IntRange(testPartitionStart, testPartitionEnd)));
-      Parameters.Add(new FixedValueParameter<ReadOnlyItemList<ITransformation>>(TransformationsParameterName, "", transformationsList.AsReadOnly()));
-
-      TransformationsParameter.Hidden = true;
 
       ((ValueParameter<Dataset>)DatasetParameter).ReactOnValueToStringChangedAndValueItemImageChanged = false;
@@ -161,5 +144,4 @@
       TrainingPartition.ValueChanged += new EventHandler(Parameter_ValueChanged);
       TestPartition.ValueChanged += new EventHandler(Parameter_ValueChanged);
-      TransformationsParameter.ValueChanged += new EventHandler(Parameter_ValueChanged);
     }
 
Index: stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Regression/RegressionProblemData.cs
===================================================================
--- stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Regression/RegressionProblemData.cs	(revision 11157)
+++ stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Regression/RegressionProblemData.cs	(revision 11158)
@@ -137,6 +137,6 @@
     }
 
-    public RegressionProblemData(Dataset dataset, IEnumerable<string> allowedInputVariables, string targetVariable, IEnumerable<ITransformation> transformations = null)
-      : base(dataset, allowedInputVariables, transformations ?? Enumerable.Empty<ITransformation>()) {
+    public RegressionProblemData(Dataset dataset, IEnumerable<string> allowedInputVariables, string targetVariable)
+      : base(dataset, allowedInputVariables) {
       var variables = InputVariables.Select(x => x.AsReadOnly()).ToList();
       Parameters.Add(new ConstrainedValueParameter<StringValue>(TargetVariableParameterName, new ItemSet<StringValue>(variables), variables.Where(x => x.Value == targetVariable).First()));
Index: stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/TimeSeriesPrognosis/TimeSeriesPrognosisProblemData.cs
===================================================================
--- stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/TimeSeriesPrognosis/TimeSeriesPrognosisProblemData.cs	(revision 11157)
+++ stable/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/TimeSeriesPrognosis/TimeSeriesPrognosisProblemData.cs	(revision 11158)
@@ -1582,6 +1582,6 @@
       TrainingPartition.Start = 50;
     }
-    public TimeSeriesPrognosisProblemData(Dataset dataset, IEnumerable<string> allowedInputVariables, string targetVariable, IEnumerable<ITransformation> transformations = null)
-      : base(dataset, allowedInputVariables, targetVariable, transformations ?? Enumerable.Empty<ITransformation>()) {
+    public TimeSeriesPrognosisProblemData(Dataset dataset, IEnumerable<string> allowedInputVariables, string targetVariable)
+      : base(dataset, allowedInputVariables, targetVariable) {
       Parameters.Add(new FixedValueParameter<IntValue>(TrainingHorizonParameterName, "Specifies the horizon (how far the prognosis reaches in the future) for each training sample.", new IntValue(1)));
       Parameters.Add(new FixedValueParameter<IntValue>(TestHorizonParameterName, "Specifies the horizon (how far the prognosis reaches in the future) for each test sample.", new IntValue(1)));
@@ -1643,7 +1643,7 @@
 
       var trainingDataStart = TrainingIndices.First();
-
+      
       base.AdjustProblemDataProperties(problemData);
-
+      
       TestPartition.Start = trainingDataStart;
 
