Changeset 13089 for branches/ClassificationModelComparison/HeuristicLab.Algorithms.DataAnalysis

Timestamp:

10/29/15 19:48:17 (8 years ago)

Author:

gkronber

Message:

#1998

• deleted obsolete version of OneR algorithm (also does perform worse than mkommend's implementation in my tests)
• reused the ConstantRegressionModel as ConstantClassificationModel (OK?)
• fixed a few strings here and there

Location:

branches/ClassificationModelComparison/HeuristicLab.Algorithms.DataAnalysis/3.4

Files:

• HeuristicLab.Algorithms.DataAnalysis-3.4.csproj (modified) (1 diff)
• Linear/OneR.cs (deleted)
• Linear/OneRTest.cs (modified) (2 diffs)
• Linear/ZeroR.cs (modified) (3 diffs)

branches/ClassificationModelComparison/HeuristicLab.Algorithms.DataAnalysis/3.4/HeuristicLab.Algorithms.DataAnalysis-3.4.csproj

@@ -318 +318 @@
     <Compile Include="Linear\AlglibUtil.cs" />
     <Compile Include="Linear\OneRTest.cs" />
-    <Compile Include="Linear\OneR.cs" />
     <Compile Include="Linear\OneR\OneRClassificationModel.cs" />
     <Compile Include="Linear\OneR\OneRClassificationSolution.cs" />

branches/ClassificationModelComparison/HeuristicLab.Algorithms.DataAnalysis/3.4/Linear/OneRTest.cs

@@ -34 +34 @@
   /// 1R classification algorithm.
   /// </summary>
-  [Item("OneR Classification", "1R classification algorithm.")]
+  [Item("OneR Classification", "A simple classification algorithm the searches the best single-variable split (does not support categorical features correctly).")]
   [StorableClass]
   public sealed class OneRTest : FixedDataAnalysisAlgorithm<IClassificationProblem> {
@@ -63 +63 @@
     }
 
-    public static IClassificationSolution CreateOneRSolution(IClassificationProblemData problemData, int minBucketSize) {
+    public static IClassificationSolution CreateOneRSolution(IClassificationProblemData problemData, int minBucketSize = 6) {
       var bestClassified = 0;
       List<Split> bestSplits = null;

branches/ClassificationModelComparison/HeuristicLab.Algorithms.DataAnalysis/3.4/Linear/ZeroR.cs

@@ -31 +31 @@
   /// 0R classification algorithm.
   /// </summary>
-  [Item("ZeroR", "0R classification algorithm.")]
-  [Creatable("Data Analysis")]
+  [Item("ZeroR", "The simplest possible classifier, ZeroR always predicts the majority class.")]
+  [Creatable("Data Analysis")] // TODO
   [StorableClass]
   public sealed class ZeroR : FixedDataAnalysisAlgorithm<IClassificationProblem> {
@@ -52 +52 @@
     protected override void Run() {
       var solution = CreateZeroRSolution(Problem.ProblemData);
-      Results.Add(new Result("ZeroR solution", "The 0R classifier.", solution));
+      Results.Add(new Result("ZeroR solution", "The simplest possible classifier, ZeroR always predicts the majority class.", solution));
     }
 
@@ -60 +60 @@
       var targetValues = dataset.GetDoubleValues(target, problemData.TrainingIndices);
 
+
+      // if multiple classes have the same number of observations then simply take the first one
       var dominantClass = targetValues.GroupBy(x => x).ToDictionary(g => g.Key, g => g.Count())
         .MaxItems(kvp => kvp.Value).Select(x => x.Key).First();
 
-      var model = new ConstantClassificationModel(dominantClass);
+      var model = new ConstantRegressionModel(dominantClass);
       var solution = new ConstantClassificationSolution(model, (IClassificationProblemData)problemData.Clone());
       return solution;