Index: branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/HeuristicLab.Problems.DataAnalysis-3.3.csproj
===================================================================
--- trunk/sources/HeuristicLab.Problems.DataAnalysis/3.3/HeuristicLab.Problems.DataAnalysis-3.3.csproj	(revision 5013)
+++ branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/HeuristicLab.Problems.DataAnalysis-3.3.csproj	(revision 5026)
@@ -91,4 +91,52 @@
   </PropertyGroup>
   <ItemGroup>
+    <Reference Include="ALGLIB-3.1.0, Version=3.1.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\ALGLIB-3.1.0.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.ALGLIB-3.1.0, Version=2.5.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.ALGLIB-3.1.0.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Collections-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Collections-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Common-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Common-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Common.Resources-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Common.Resources-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Core-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Core-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Data-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Data-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Encodings.RealVectorEncoding-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Encodings.RealVectorEncoding-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.LibSVM-1.6.3, Version=1.6.3.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.LibSVM-1.6.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Operators-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Operators-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Optimization-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Optimization-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Parameters-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Parameters-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Persistence-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Persistence-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.PluginInfrastructure-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.PluginInfrastructure-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="HeuristicLab.Random-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>c:\Program Files\HeuristicLab 3.3\HeuristicLab.Random-3.3.dll</HintPath>
+    </Reference>
+    <Reference Include="LibSVM-1.6.3, Version=1.6.3.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=x86">
+      <HintPath>..\..\..\..\..\..\Program Files\HeuristicLab 3.3\LibSVM-1.6.3.dll</HintPath>
+    </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core">
@@ -129,4 +177,5 @@
     <Compile Include="Evaluators\SimpleVarianceAccountedForEvaluator.cs" />
     <Compile Include="HeuristicLabProblemsDataAnalysisPlugin.cs" />
+    <Compile Include="Interfaces\ILaggedTreeNode.cs" />
     <Compile Include="Interfaces\ISingleObjectiveDataAnalysisProblem.cs" />
     <Compile Include="Interfaces\IDataAnalysisModel.cs" />
@@ -147,6 +196,8 @@
     <Compile Include="Symbolic\SymbolicSimplifier.cs" />
     <Compile Include="Symbolic\Symbols\Addition.cs" />
+    <Compile Include="Symbolic\Symbols\LaggedSymbol.cs" />
     <Compile Include="Symbolic\Symbols\Constant.cs" />
     <Compile Include="Symbolic\Symbols\ConstantTreeNode.cs" />
+    <Compile Include="Symbolic\Symbols\LaggedTreeNode.cs" />
     <Compile Include="Symbolic\Symbols\LaggedVariable.cs" />
     <Compile Include="Symbolic\Symbols\LaggedVariableTreeNode.cs" />
@@ -166,4 +217,5 @@
     <Compile Include="Symbolic\Symbols\Multiplication.cs" />
     <Compile Include="Symbolic\Symbols\Subtraction.cs" />
+    <Compile Include="Symbolic\Symbols\TimeLag.cs" />
     <Compile Include="Symbolic\Symbols\Variable.cs" />
     <Compile Include="Symbolic\Symbols\VariableTreeNode.cs" />
@@ -171,71 +223,7 @@
   </ItemGroup>
   <ItemGroup>
-    <ProjectReference Include="..\..\HeuristicLab.Collections\3.3\HeuristicLab.Collections-3.3.csproj">
-      <Project>{958B43BC-CC5C-4FA2-8628-2B3B01D890B6}</Project>
-      <Name>HeuristicLab.Collections-3.3</Name>
-    </ProjectReference>
-    <ProjectReference Include="..\..\HeuristicLab.Common.Resources\3.3\HeuristicLab.Common.Resources-3.3.csproj">
-      <Project>{0E27A536-1C4A-4624-A65E-DC4F4F23E3E1}</Project>
-      <Name>HeuristicLab.Common.Resources-3.3</Name>
-    </ProjectReference>
-    <ProjectReference Include="..\..\HeuristicLab.Common\3.3\HeuristicLab.Common-3.3.csproj">
-      <Project>{A9AD58B9-3EF9-4CC1-97E5-8D909039FF5C}</Project>
-      <Name>HeuristicLab.Common-3.3</Name>
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-    <ProjectReference Include="..\..\HeuristicLab.Core\3.3\HeuristicLab.Core-3.3.csproj">
-      <Project>{C36BD924-A541-4A00-AFA8-41701378DDC5}</Project>
-      <Name>HeuristicLab.Core-3.3</Name>
-    </ProjectReference>
-    <ProjectReference Include="..\..\HeuristicLab.Data\3.3\HeuristicLab.Data-3.3.csproj">
-      <Project>{BBAB9DF5-5EF3-4BA8-ADE9-B36E82114937}</Project>
-      <Name>HeuristicLab.Data-3.3</Name>
-    </ProjectReference>
-    <ProjectReference Include="..\..\HeuristicLab.Encodings.RealVectorEncoding\3.3\HeuristicLab.Encodings.RealVectorEncoding-3.3.csproj">
-      <Project>{BB6D334A-4BB6-4674-9883-31A6EBB32CAB}</Project>
-      <Name>HeuristicLab.Encodings.RealVectorEncoding-3.3</Name>
-    </ProjectReference>
     <ProjectReference Include="..\..\HeuristicLab.Encodings.SymbolicExpressionTreeEncoding\3.3\HeuristicLab.Encodings.SymbolicExpressionTreeEncoding-3.3.csproj">
       <Project>{125D3006-67F5-48CB-913E-73C0548F17FA}</Project>
       <Name>HeuristicLab.Encodings.SymbolicExpressionTreeEncoding-3.3</Name>
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-      <Project>{FC841674-62A7-4055-BE91-E41944B6C606}</Project>
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Index: branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Interfaces/ILaggedTreeNode.cs
===================================================================
--- branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Interfaces/ILaggedTreeNode.cs	(revision 5026)
+++ branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Interfaces/ILaggedTreeNode.cs	(revision 5026)
@@ -0,0 +1,28 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2010 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
+namespace HeuristicLab.Problems.DataAnalysis {
+  public interface ILaggedTreeNode : ISymbolicExpressionTreeNode {
+    int Lag { get; set; }
+  }
+}
Index: branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/FullFunctionalExpressionGrammar.cs
===================================================================
--- trunk/sources/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/FullFunctionalExpressionGrammar.cs	(revision 5013)
+++ branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/FullFunctionalExpressionGrammar.cs	(revision 5026)
@@ -60,4 +60,6 @@
       var or = new Or();
       var not = new Not();
+      var timeLag = new TimeLag();
+      timeLag.InitialFrequency = 0.0;
       var constant = new Constant();
       constant.MinValue = -20;
@@ -67,6 +69,6 @@
       laggedVariable.InitialFrequency = 0.0;
 
-      var allSymbols = new List<Symbol>() { add, sub, mul, div, mean, sin, cos, tan, log, exp, @if, gt, lt, and, or, not, constant, variableSymbol, laggedVariable };
-      var unaryFunctionSymbols = new List<Symbol>() { sin, cos, tan, log, exp, not };
+      var allSymbols = new List<Symbol>() { add, sub, mul, div, mean, sin, cos, tan, log, exp, @if, gt, lt, and, or, not, timeLag, constant, variableSymbol, laggedVariable };
+      var unaryFunctionSymbols = new List<Symbol>() { sin, cos, tan, log, exp, not, timeLag };
       var binaryFunctionSymbols = new List<Symbol>() { gt, lt };
       var functionSymbols = new List<Symbol>() { add, sub, mul, div, mean, and, or };
Index: branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/SimpleArithmeticExpressionInterpreter.cs
===================================================================
--- trunk/sources/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/SimpleArithmeticExpressionInterpreter.cs	(revision 5013)
+++ branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/SimpleArithmeticExpressionInterpreter.cs	(revision 5026)
@@ -66,4 +66,6 @@
       public const byte Constant = 20;
       public const byte Arg = 21;
+
+      public const byte TimeLag = 22;
     }
 
@@ -90,4 +92,5 @@
       { typeof(Constant), OpCodes.Constant },
       { typeof(Argument), OpCodes.Arg },
+      { typeof(TimeLag), OpCodes.TimeLag},
     };
     private const int ARGUMENT_STACK_SIZE = 1024;
@@ -290,4 +293,15 @@
             return constTreeNode.Value;
           }
+        case OpCodes.TimeLag: {
+            var timeLagTreeNode = (LaggedTreeNode)currentInstr.dynamicNode;
+            row += timeLagTreeNode.Lag;
+            if (row < 0 || row >= dataset.Rows) {
+              row -= timeLagTreeNode.Lag;
+              return double.NaN;
+            }
+            double result = Evaluate();
+            row -= timeLagTreeNode.Lag;
+            return result;
+          }
         default: throw new NotSupportedException();
       }
Index: branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/LaggedSymbol.cs
===================================================================
--- branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/LaggedSymbol.cs	(revision 5026)
+++ branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/LaggedSymbol.cs	(revision 5026)
@@ -0,0 +1,44 @@
+﻿using HeuristicLab.Common;
+using HeuristicLab.Core;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Symbols;
+using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Symbols {
+  [StorableClass]
+  [Item("LaggedSymbol", "Represents a symblol whose evaluation is shifted.")]
+  public abstract class LaggedSymbol : Symbol {
+    [Storable]
+    private int minLag;
+    public virtual int MinLag {
+      get { return minLag; }
+      set { minLag = value; }
+    }
+    [Storable]
+    private int maxLag;
+    public virtual int MaxLag {
+      get { return maxLag; }
+      set { maxLag = value; }
+    }
+
+    [StorableConstructor]
+    protected LaggedSymbol(bool deserializing) : base(deserializing) { }
+    protected LaggedSymbol(LaggedSymbol original, Cloner cloner)
+      : base(original, cloner) {
+      minLag = original.minLag;
+      maxLag = original.maxLag;
+    }
+    protected LaggedSymbol()
+      : base("LaggedSymbol", "Represents a symbol whose evaluation is shifted.") {
+      minLag = -1; maxLag = -1;
+    }
+    protected LaggedSymbol(string name, string description)
+      : base(name, description) {
+      minLag = -1; maxLag = -1;
+    }
+
+    public override SymbolicExpressionTreeNode CreateTreeNode() {
+      return new LaggedTreeNode(this);
+    }
+  }
+}
Index: branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/LaggedTreeNode.cs
===================================================================
--- branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/LaggedTreeNode.cs	(revision 5026)
+++ branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/LaggedTreeNode.cs	(revision 5026)
@@ -0,0 +1,70 @@
+#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2010 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using HeuristicLab.Common;
+using HeuristicLab.Core;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
+using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Symbols {
+  [StorableClass]
+  public class LaggedTreeNode : SymbolicExpressionTreeNode, ILaggedTreeNode {
+    public new LaggedSymbol Symbol {
+      get { return (LaggedSymbol)base.Symbol; }
+    }
+    [Storable]
+    private int lag;
+    public int Lag {
+      get { return lag; }
+      set { lag = value; }
+    }
+
+    [StorableConstructor]
+    protected LaggedTreeNode(bool deserializing) : base(deserializing) { }
+    protected LaggedTreeNode(LaggedTreeNode original, Cloner cloner)
+      : base(original, cloner) {
+      lag = original.lag;
+    }
+    public LaggedTreeNode(LaggedSymbol timeLagSymbol) : base(timeLagSymbol) { }
+
+    public override bool HasLocalParameters {
+      get { return true; }
+    }
+
+    public override void ResetLocalParameters(IRandom random) {
+      base.ResetLocalParameters(random);
+      lag = random.Next(Symbol.MinLag, Symbol.MaxLag + 1);
+    }
+
+    public override void ShakeLocalParameters(IRandom random, double shakingFactor) {
+      base.ShakeLocalParameters(random, shakingFactor);
+      lag = Math.Min(Symbol.MaxLag, Math.Max(Symbol.MinLag, lag + random.Next(-1, 2)));
+    }
+
+    public override IDeepCloneable Clone(Cloner cloner) {
+      return new LaggedTreeNode(this, cloner);
+    }
+
+    public override string ToString() {
+      return base.ToString() + " " + lag.ToString();
+    }
+  }
+}
Index: branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/LaggedVariableTreeNode.cs
===================================================================
--- trunk/sources/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/LaggedVariableTreeNode.cs	(revision 5013)
+++ branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/LaggedVariableTreeNode.cs	(revision 5026)
@@ -26,5 +26,5 @@
 namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Symbols {
   [StorableClass]
-  public sealed class LaggedVariableTreeNode : VariableTreeNode {
+  public sealed class LaggedVariableTreeNode : VariableTreeNode, ILaggedTreeNode {
     public new LaggedVariable Symbol {
       get { return (LaggedVariable)base.Symbol; }
Index: branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/TimeLag.cs
===================================================================
--- branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/TimeLag.cs	(revision 5026)
+++ branches/GP.Symbols (TimeLag, Diff, Integral)/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Symbols/TimeLag.cs	(revision 5026)
@@ -0,0 +1,38 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2010 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using HeuristicLab.Common;
+using HeuristicLab.Core;
+using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Symbols {
+  [StorableClass]
+  [Item("TimeLag", "Represents a symblol whose evaluation is shifted.")]
+  public sealed class TimeLag : LaggedSymbol {
+    [StorableConstructor]
+    private TimeLag(bool deserializing) : base(deserializing) { }
+    private TimeLag(TimeLag original, Cloner cloner) : base(original, cloner) { }
+    public override IDeepCloneable Clone(Cloner cloner) {
+      return new TimeLag(this, cloner);
+    }
+    public TimeLag() : base("TimeLag", "Represents a symblol whose evaluation is shifted.") { }
+  }
+}
