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source: branches/DataAnalysis/HeuristicLab.Problems.DataAnalysis/3.3/Operators/CovariantParsimonyPressure.cs @ 4350

Last change on this file since 4350 was 4350, checked in by gkronber, 14 years ago

added minimal size parameter for pruning operator. #1142
File size: 11.9 KB
Line 
1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2010 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
4 *
5 * This file is part of HeuristicLab.
6 *
7 * HeuristicLab is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
11 *
12 * HeuristicLab is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
19 */
20#endregion
21
22using System;
23using System.Linq;
24using alglib;
25using HeuristicLab.Core;
26using HeuristicLab.Data;
27using HeuristicLab.Operators;
28using HeuristicLab.Optimization;
29using HeuristicLab.Parameters;
30using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
31using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
32using System.Collections.Generic;
33using HeuristicLab.Problems.DataAnalysis.Evaluators;
34using HeuristicLab.Analysis;
35
36namespace HeuristicLab.Problems.DataAnalysis.Operators {
37  [Item("Covariant Parsimony Pressure", "Covariant Parsimony Pressure.")]
38  [StorableClass]
39  public class CovariantParsimonyPressure : SingleSuccessorOperator {
40    public IScopeTreeLookupParameter<SymbolicExpressionTree> SymbolicExpressionTreeParameter {
41      get { return (IScopeTreeLookupParameter<SymbolicExpressionTree>)Parameters["SymbolicExpressionTree"]; }
42    }
43    public IScopeTreeLookupParameter<DoubleValue> QualityParameter {
44      get { return (IScopeTreeLookupParameter<DoubleValue>)Parameters["Quality"]; }
45    }
46    public IScopeTreeLookupParameter<DoubleValue> AdjustedQualityParameter {
47      get { return (IScopeTreeLookupParameter<DoubleValue>)Parameters["AdjustedQuality"]; }
48    }
49    public ILookupParameter<BoolValue> MaximizationParameter {
50      get { return (ILookupParameter<BoolValue>)Parameters["Maximization"]; }
51    }
52    public IValueLookupParameter<DoubleValue> KParameter {
53      get { return (IValueLookupParameter<DoubleValue>)Parameters["K"]; }
54    }
55    public ILookupParameter<DoubleValue> CParameter {
56      get { return (ILookupParameter<DoubleValue>)Parameters["C"]; }
57    }
58    public ILookupParameter<IntValue> GenerationsParameter {
59      get { return (ILookupParameter<IntValue>)Parameters["Generations"]; }
60    }
61    public IValueLookupParameter<IntValue> FirstGenerationParameter {
62      get { return (IValueLookupParameter<IntValue>)Parameters["FirstGenerationParameter"]; }
63    }
64    public IValueLookupParameter<BoolValue> ApplyParsimonyPressureParameter {
65      get { return (IValueLookupParameter<BoolValue>)Parameters["ApplyParsimonyPressure"]; }
66    }
67    public ILookupParameter<DoubleValue> LengthCorrelationParameter {
68      get { return (ILookupParameter<DoubleValue>)Parameters["Correlation(Length, AdjustedFitness)"]; }
69    }
70    public ILookupParameter<DoubleValue> FitnessCorrelationParameter {
71      get { return (ILookupParameter<DoubleValue>)Parameters["Correlation(Fitness, AdjustedFitness)"]; }
72    }
73    public IValueLookupParameter<PercentValue> ComplexityAdaptionParameter {
74      get { return (IValueLookupParameter<PercentValue>)Parameters["ComplexityAdaption"]; }
75    }
76    public IValueLookupParameter<BoolValue> InvertComplexityAdaptionParameter {
77      get { return (IValueLookupParameter<BoolValue>)Parameters["InvertComplexityAdaption"]; }
78    }
79    public IValueLookupParameter<DoubleValue> MinAverageSizeParameter {
80      get { return (IValueLookupParameter<DoubleValue>)Parameters["MinAverageSize"]; }
81    }
82
83    public CovariantParsimonyPressure(bool deserializing) : base(deserializing) { }
84    public CovariantParsimonyPressure()
85      : base() {
86      Parameters.Add(new ScopeTreeLookupParameter<SymbolicExpressionTree>("SymbolicExpressionTree"));
87      Parameters.Add(new ScopeTreeLookupParameter<DoubleValue>("Quality"));
88      Parameters.Add(new ScopeTreeLookupParameter<DoubleValue>("AdjustedQuality"));
89      Parameters.Add(new LookupParameter<BoolValue>("Maximization"));
90      Parameters.Add(new ValueLookupParameter<DoubleValue>("K", new DoubleValue(1.0)));
91      Parameters.Add(new LookupParameter<IntValue>("Generations"));
92      Parameters.Add(new ValueLookupParameter<IntValue>("FirstGenerationParameter", new IntValue(1)));
93      Parameters.Add(new ValueLookupParameter<BoolValue>("ApplyParsimonyPressure"));
94      Parameters.Add(new ValueLookupParameter<PercentValue>("ComplexityAdaption", new PercentValue(-0.01)));
95      Parameters.Add(new LookupParameter<DoubleValue>("Correlation(Length, AdjustedFitness)"));
96      Parameters.Add(new LookupParameter<DoubleValue>("Correlation(Fitness, AdjustedFitness)"));
97      Parameters.Add(new ValueLookupParameter<DoubleValue>("MinAverageSize", new DoubleValue(15)));
98      Parameters.Add(new LookupParameter<DoubleValue>("C"));
99      Parameters.Add(new ValueLookupParameter<BoolValue>("InvertComplexityAdaption"));
100    }
101
102    [StorableHook(Persistence.Default.CompositeSerializers.Storable.HookType.AfterDeserialization)]
103    private void AfterDeserialization() {
104      if (!Parameters.ContainsKey("Maximization"))
105        Parameters.Add(new LookupParameter<BoolValue>("Maximization"));
106      if (!Parameters.ContainsKey("K"))
107        Parameters.Add(new ValueLookupParameter<DoubleValue>("K", new DoubleValue(1.0)));
108      if (!Parameters.ContainsKey("AdjustedQuality")) {
109        Parameters.Add(new ScopeTreeLookupParameter<DoubleValue>("AdjustedQuality"));
110      }
111      if (!Parameters.ContainsKey("Generations")) {
112        Parameters.Add(new LookupParameter<IntValue>("Generations"));
113      }
114      if (!Parameters.ContainsKey("FirstGenerationParameter")) {
115        Parameters.Add(new ValueLookupParameter<IntValue>("FirstGenerationParameter", new IntValue(1)));
116      }
117      if (!Parameters.ContainsKey("ApplyParsimonyPressure")) {
118        Parameters.Add(new ValueLookupParameter<BoolValue>("ApplyParsimonyPressure"));
119      }
120      if (!Parameters.ContainsKey("ComplexityAdaption")) {
121        Parameters.Add(new ValueLookupParameter<PercentValue>("ComplexityAdaption", new PercentValue(-0.01)));
122      }
123      if (!Parameters.ContainsKey("MinAverageSize")) {
124        Parameters.Add(new ValueLookupParameter<DoubleValue>("MinAverageSize", new DoubleValue(15)));
125      }
126      if (!Parameters.ContainsKey("C")) {
127        Parameters.Add(new LookupParameter<DoubleValue>("C"));
128      }
129      if (!Parameters.ContainsKey("InvertComplexityAdaption")) {
130        Parameters.Add(new ValueLookupParameter<BoolValue>("InvertComplexityAdaption"));
131      }
132    }
133
134    public override IOperation Apply() {
135      ItemArray<SymbolicExpressionTree> trees = SymbolicExpressionTreeParameter.ActualValue;
136      ItemArray<DoubleValue> qualities = QualityParameter.ActualValue;
137      // always apply Parsimony pressure if overfitting has been detected
138      // otherwise appliy PP only when we are currently overfitting
139      if (GenerationsParameter.ActualValue != null && GenerationsParameter.ActualValue.Value >= FirstGenerationParameter.ActualValue.Value &&
140           ApplyParsimonyPressureParameter.ActualValue.Value == true) {
141        var lengths = from tree in trees
142                      select tree.Size;
143        double k = KParameter.ActualValue.Value;
144
145        // calculate cov(f, l) and cov(l, l^k)
146        OnlineCovarianceEvaluator lengthFitnessCovEvaluator = new OnlineCovarianceEvaluator();
147        OnlineCovarianceEvaluator lengthAdjLengthCovEvaluator = new OnlineCovarianceEvaluator();
148        OnlineMeanAndVarianceCalculator lengthMeanCalculator = new OnlineMeanAndVarianceCalculator();
149        OnlineMeanAndVarianceCalculator fitnessMeanCalculator = new OnlineMeanAndVarianceCalculator();
150        OnlineMeanAndVarianceCalculator adjLengthMeanCalculator = new OnlineMeanAndVarianceCalculator();
151        var lengthEnumerator = lengths.GetEnumerator();
152        var qualityEnumerator = qualities.GetEnumerator();
153        while (lengthEnumerator.MoveNext() & qualityEnumerator.MoveNext()) {
154          double fitness = qualityEnumerator.Current.Value;
155          if (!MaximizationParameter.ActualValue.Value) {
156            // use f = 1 / (1 + quality) for minimization problems
157            fitness = 1.0 / (1.0 + fitness);
158          }
159          lengthFitnessCovEvaluator.Add(lengthEnumerator.Current, fitness);
160          lengthAdjLengthCovEvaluator.Add(lengthEnumerator.Current, Math.Pow(lengthEnumerator.Current, k));
161          lengthMeanCalculator.Add(lengthEnumerator.Current);
162          fitnessMeanCalculator.Add(fitness);
163          adjLengthMeanCalculator.Add(Math.Pow(lengthEnumerator.Current, k));
164        }
165
166        //double sizeAdaption = lengthMeanCalculator.Mean * ComplexityAdaptionParameter.ActualValue.Value;
167        double sizeAdaption = 100.0 * ComplexityAdaptionParameter.ActualValue.Value;
168        if (InvertComplexityAdaptionParameter.ActualValue != null && InvertComplexityAdaptionParameter.ActualValue.Value) {
169          sizeAdaption = -sizeAdaption;
170        }
171        if (lengthMeanCalculator.Mean + sizeAdaption < MinAverageSizeParameter.ActualValue.Value)
172          sizeAdaption = MinAverageSizeParameter.ActualValue.Value - lengthMeanCalculator.Mean;
173
174        //            cov(l, f) - (g(t+1) - mu(t)) avgF
175        // c(t) =  --------------------------------------------
176        //           cov(l, l^k) - (g(t+1) - mu(t)) E[l^k]
177        double c = lengthFitnessCovEvaluator.Covariance - sizeAdaption * fitnessMeanCalculator.Mean;
178        c /= lengthAdjLengthCovEvaluator.Covariance - sizeAdaption * adjLengthMeanCalculator.Mean;
179
180        CParameter.ActualValue = new DoubleValue(c);
181
182        // adjust fitness
183        bool maximization = MaximizationParameter.ActualValue.Value;
184
185        lengthEnumerator = lengths.GetEnumerator();
186        qualityEnumerator = qualities.GetEnumerator();
187        int i = 0;
188        ItemArray<DoubleValue> adjQualities = new ItemArray<DoubleValue>(qualities.Length);
189
190        while (lengthEnumerator.MoveNext() & qualityEnumerator.MoveNext()) {
191          adjQualities[i++] = new DoubleValue(qualityEnumerator.Current.Value - c * Math.Pow(lengthEnumerator.Current, k));
192        }
193        AdjustedQualityParameter.ActualValue = adjQualities;
194        double[] lengthArr = lengths.Select(x => (double)x).ToArray<double>();
195
196        double[] adjFitess = (from f in AdjustedQualityParameter.ActualValue
197                              select f.Value).ToArray<double>();
198        double[] fitnessArr = (from f in QualityParameter.ActualValue
199                               let normFit = maximization ? f.Value : 1.0 / (1.0 + f.Value)
200                               select normFit).ToArray<double>();
201
202        LengthCorrelationParameter.ActualValue = new DoubleValue(alglib.correlation.spearmanrankcorrelation(lengthArr, adjFitess, lengthArr.Length));
203        FitnessCorrelationParameter.ActualValue = new DoubleValue(alglib.correlation.spearmanrankcorrelation(fitnessArr, adjFitess, lengthArr.Length));
204
205      } else {
206        CParameter.ActualValue = new DoubleValue(0.0);
207        // adjusted fitness is equal to fitness
208        AdjustedQualityParameter.ActualValue = (ItemArray<DoubleValue>)QualityParameter.ActualValue.Clone();
209        FitnessCorrelationParameter.ActualValue = new DoubleValue(1.0);
210
211        double[] lengths = (from tree in trees
212                            select (double)tree.Size).ToArray<double>();
213
214        double[] fitess = (from f in AdjustedQualityParameter.ActualValue
215                           select f.Value).ToArray<double>();
216
217        LengthCorrelationParameter.ActualValue = new DoubleValue(alglib.correlation.spearmanrankcorrelation(lengths, fitess, lengths.Length));
218      }
219      return base.Apply();
220    }
221  }
222}
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