private List <ClassifierInfo> CreateEnsemble(Node current)
{
List <ClassifierInfo> ensemble = new List <ClassifierInfo>();
foreach (Dataset currentTrainingSet in this._trainingSets)
{
Dataset local = GetLocalFlatDataset(current, currentTrainingSet);
_algorithm.Dataset = local;
IClassifier currentClassifier = _algorithm.CreateClassifier();
double currentQyuality = _evaluator.CalculateMeasure(ConfusionMatrix.GetConfusionMatrixes(currentClassifier, local));
ClassifierInfo info = new ClassifierInfo()
{
Classifier = currentClassifier, Desc = current.Name + ":" + currentTrainingSet.Metadata.DatasetName, Quality = currentQyuality
};
if (_fireEvents)
{
ClassifierInfoEventArgs args = new ClassifierInfoEventArgs()
{
Info = info
};
this.onPostClassifierConstruction(current, args);
}
ensemble.Add(info);
}
return(ensemble);
}
public void PutClassifier(string label, ClassifierInfo info)
{
if (!this._modelMapping.Keys.Contains(label))
{
this._modelMapping.Add(label, new List <ClassifierInfo>());
}
this._modelMapping[label].Add(info);
}
public int Classify(List <ClassifierInfo> classifiersInfo, Data.Example example)
{
ClassifierInfo best = classifiersInfo[0];
foreach (ClassifierInfo current in classifiersInfo)
{
if (current.Quality > best.Quality)
{
best = current;
}
}
return(best.Classifier.Classify(example).Label);
}
public int Classify(List <ClassifierInfo> classifiersInfo, List <Data.Example> examples)
{
ClassifierInfo best = classifiersInfo[0];
foreach (ClassifierInfo current in classifiersInfo)
{
if (current.Quality > best.Quality)
{
best = current;
}
}
Data.Example bestExample = examples.Find(e => best.Desc.Contains(e.Metadata.DatasetName));
return(best.Classifier.Classify(bestExample).Label);
}
public static ClassifierInfo DeserializeClassifier(string desc)
{
ClassifierInfo info = null;
string path = @"temp\" + desc;
using (StreamReader reader = new StreamReader(path))
{
BinaryFormatter formatter = new BinaryFormatter();
info = formatter.Deserialize(reader.BaseStream) as ClassifierInfo;
reader.Close();
File.Delete(path);
}
return(info);
}
public static IClassifier CreateMetaClassifier(IClassificationAlgorithm algorithm, List <Dataset> trainingsets, List <ClassifierInfo> ensemble)
{
List <Data.Attribute> metaAttributes = new List <Data.Attribute>();
for (int i = 0; i < ensemble.Count; i++)
{
metaAttributes.Add(new Data.Attribute(ensemble[i].Desc, i, new string[] { "Yes", "No" }));
}
Data.Attribute metaClass = new Data.Attribute("Class", ensemble.Count, new string[] { "Yes", "No" });
Metadata metadata = new Metadata("metaClassifier", metaAttributes.ToArray(), metaClass);
List <Example> metaExamples = new List <Example>();
int counter = 0;
foreach (Example example in trainingsets[0])
{
List <int> predictions = new List <int>();
for (int infoIndex = 0; infoIndex < ensemble.Count; infoIndex++)
{
ClassifierInfo info = ensemble[infoIndex];
int predictoin = info.Classifier.Classify(trainingsets[infoIndex][example.Index]).Label;
predictions.Add(predictoin);
}
Example metaExample = new Example(metadata, counter++, predictions.ToArray(), trainingsets[0][example.Index].Label);
metaExamples.Add(metaExample);
}
Dataset metaDataset = new Dataset(metadata);
metaDataset.SetExamples(metaExamples.ToArray());
algorithm.Dataset = metaDataset;
IClassifier classifier = algorithm.CreateClassifier();
return(classifier);
}
public static void SerializeClassifier(ClassifierInfo info)
{
if (!Directory.Exists("temp"))
{
System.IO.Directory.CreateDirectory("temp");
}
string path = @"temp\" + info.Desc;
if (File.Exists(path))
{
File.Delete(path);
}
using (StreamWriter writer = new StreamWriter(@"temp\" + info.Desc))
{
BinaryFormatter formatter = new BinaryFormatter();
formatter.Serialize(writer.BaseStream, info);
}
}
public int Classify(List <ClassifierInfo> classifiersInfo, List <Data.Example> examples)
{
IClassifier metaClassifier = classifiersInfo.Last().Classifier;
List <int> predictionValues = new List <int>();
for (int i = 0; i < classifiersInfo.Count - 1; i++)
{
ClassifierInfo info = classifiersInfo[i];
Data.Example example = examples.Find(e => info.Desc.Contains(e.Metadata.DatasetName));
int prediction = info.Classifier.Classify(example).Label;
predictionValues.Add(prediction);
}
Data.Example metaExample = new Data.Example(null, -1, predictionValues.ToArray(), -1);
int finalPredction = metaClassifier.Classify(metaExample).Label;
return(finalPredction);
}
public Model.Hierarchical.IHierarchicalClassifier CreateClassifier()
{
ClassHierarchy hierarchy = ((Data.HierarchicalAttribute) this._trainingSets[0].Metadata.Target).Hierarchy;
LocalPerNodeClassifier localClassifer = new LocalPerNodeClassifier(hierarchy, _ensembleStrategy);
Node current = hierarchy.Root;
Queue <Node> queue = new Queue <Node>();
foreach (Node node in hierarchy.GetNodes(current.Children))
{
queue.Enqueue(node);
}
int counter = 1;
while (queue.Count != 0)
{
current = queue.Dequeue();
if (localClassifer.Contains(current.Name))
{
continue;
}
List <ClassifierInfo> ensemble = CreateEnsemble(current);
if (_ensembleStrategy is EnsembleStrategy.EnsembleStackClassificationStrategy)
{
List <Dataset> localDatasets = new List <Dataset>();
foreach (Dataset trainingSet in this._trainingSets)
{
localDatasets.Add(GetLocalFlatDataset(current, trainingSet));
}
IClassifier metaClassifier = EnsembleStrategy.EnsembleStackClassificationStrategy.CreateMetaClassifier(this._algorithm, localDatasets, ensemble);
ClassifierInfo metaInfo = new ClassifierInfo()
{
Desc = "metaClassifier", Classifier = metaClassifier, Quality = -1
};
ensemble.Add(metaInfo);
}
if (_serialize)
{
IO.Serializer.SerializeEnsmeble(ensemble, current.Name);
localClassifer.PutEnsemble(current.Name, null);
}
else
{
localClassifer.PutEnsemble(current.Name, ensemble);
}
if (_fireEvents)
{
this.onPostNodeProcessing(current, new NodeCounterEventArgs()
{
Counter = counter
});
}
counter++;
if (current.Children != null)
{
foreach (string child in current.Children)
{
if (!queue.Contains(hierarchy[child]))
{
queue.Enqueue(hierarchy[child]);
}
}
}
}
if (_serialize)
{
foreach (Node node in hierarchy.GetDescendants(hierarchy.Root))
{
localClassifer.PutEnsemble(node.Name, IO.Serializer.DeserializeEnsemble(node.Name));
}
}
return(localClassifer);
}
