use of de.lmu.ifi.dbs.elki.result.outlier.OutlierScoreMeta in project elki by elki-project.
the class ParallelKNNOutlier method run.
public OutlierResult run(Database database, Relation<O> relation) {
DBIDs ids = relation.getDBIDs();
WritableDoubleDataStore store = DataStoreUtil.makeDoubleStorage(ids, DataStoreFactory.HINT_DB);
DistanceQuery<O> distq = database.getDistanceQuery(relation, getDistanceFunction());
KNNQuery<O> knnq = database.getKNNQuery(distq, k + 1);
// Compute the kNN
KNNProcessor<O> knnm = new KNNProcessor<>(k + 1, knnq);
SharedObject<KNNList> knnv = new SharedObject<>();
knnm.connectKNNOutput(knnv);
// Extract the k-distance
KDistanceProcessor kdistm = new KDistanceProcessor(k + 1);
SharedDouble kdistv = new SharedDouble();
kdistm.connectKNNInput(knnv);
kdistm.connectOutput(kdistv);
// Store in outlier scores
WriteDoubleDataStoreProcessor storem = new WriteDoubleDataStoreProcessor(store);
storem.connectInput(kdistv);
// Gather statistics
DoubleMinMaxProcessor mmm = new DoubleMinMaxProcessor();
mmm.connectInput(kdistv);
ParallelExecutor.run(ids, knnm, kdistm, storem, mmm);
DoubleMinMax minmax = mmm.getMinMax();
DoubleRelation scoreres = new MaterializedDoubleRelation("kNN Outlier Score", "knn-outlier", store, ids);
OutlierScoreMeta meta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 0.0);
return new OutlierResult(meta, scoreres);
}
use of de.lmu.ifi.dbs.elki.result.outlier.OutlierScoreMeta in project elki by elki-project.
the class SimplifiedLOF method run.
/**
* Run the Simple LOF algorithm.
*
* @param database Database to query
* @param relation Data to process
* @return LOF outlier result
*/
public OutlierResult run(Database database, Relation<O> relation) {
StepProgress stepprog = LOG.isVerbose() ? new StepProgress("Simplified LOF", 3) : null;
DBIDs ids = relation.getDBIDs();
LOG.beginStep(stepprog, 1, "Materializing neighborhoods w.r.t. distance function.");
KNNQuery<O> knnq = DatabaseUtil.precomputedKNNQuery(database, relation, getDistanceFunction(), k);
// Compute LRDs
LOG.beginStep(stepprog, 2, "Computing densities.");
WritableDoubleDataStore dens = DataStoreUtil.makeDoubleStorage(ids, DataStoreFactory.HINT_HOT | DataStoreFactory.HINT_TEMP);
computeSimplifiedLRDs(ids, knnq, dens);
// compute LOF_SCORE of each db object
LOG.beginStep(stepprog, 3, "Computing SLOFs.");
WritableDoubleDataStore lofs = DataStoreUtil.makeDoubleStorage(ids, DataStoreFactory.HINT_STATIC);
DoubleMinMax lofminmax = new DoubleMinMax();
computeSimplifiedLOFs(ids, knnq, dens, lofs, lofminmax);
LOG.setCompleted(stepprog);
// Build result representation.
DoubleRelation scoreResult = new MaterializedDoubleRelation("Simplified Local Outlier Factor", "simplified-lof-outlier", lofs, ids);
OutlierScoreMeta scoreMeta = new QuotientOutlierScoreMeta(lofminmax.getMin(), lofminmax.getMax(), 0., Double.POSITIVE_INFINITY, 1.);
OutlierResult result = new OutlierResult(scoreMeta, scoreResult);
return result;
}
use of de.lmu.ifi.dbs.elki.result.outlier.OutlierScoreMeta in project elki by elki-project.
the class VarianceOfVolume method run.
/**
* Runs the VOV algorithm on the given database.
*
* @param database Database to query
* @param relation Data to process
* @return VOV outlier result
*/
public OutlierResult run(Database database, Relation<O> relation) {
StepProgress stepprog = LOG.isVerbose() ? new StepProgress("VOV", 3) : null;
DBIDs ids = relation.getDBIDs();
int dim = RelationUtil.dimensionality(relation);
LOG.beginStep(stepprog, 1, "Materializing nearest-neighbor sets.");
KNNQuery<O> knnq = DatabaseUtil.precomputedKNNQuery(database, relation, getDistanceFunction(), k);
// Compute Volumes
LOG.beginStep(stepprog, 2, "Computing Volumes.");
WritableDoubleDataStore vols = DataStoreUtil.makeDoubleStorage(ids, DataStoreFactory.HINT_HOT | DataStoreFactory.HINT_TEMP);
computeVolumes(knnq, dim, ids, vols);
// compute VOV of each object
LOG.beginStep(stepprog, 3, "Computing Variance of Volumes (VOV).");
WritableDoubleDataStore vovs = DataStoreUtil.makeDoubleStorage(ids, DataStoreFactory.HINT_HOT | DataStoreFactory.HINT_DB);
// track the maximum value for normalization.
DoubleMinMax vovminmax = new DoubleMinMax();
computeVOVs(knnq, ids, vols, vovs, vovminmax);
LOG.setCompleted(stepprog);
// Build result representation.
DoubleRelation scoreResult = new MaterializedDoubleRelation("Variance of Volume", "vov-outlier", vovs, ids);
OutlierScoreMeta scoreMeta = new BasicOutlierScoreMeta(vovminmax.getMin(), vovminmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 0.0);
return new OutlierResult(scoreMeta, scoreResult);
}
use of de.lmu.ifi.dbs.elki.result.outlier.OutlierScoreMeta in project elki by elki-project.
the class CTLuScatterplotOutlier method run.
/**
* Main method.
*
* @param database Database
* @param nrel Neighborhood relation
* @param relation Data relation (1d!)
* @return Outlier detection result
*/
public OutlierResult run(Database database, Relation<N> nrel, Relation<? extends NumberVector> relation) {
final NeighborSetPredicate npred = getNeighborSetPredicateFactory().instantiate(database, nrel);
WritableDoubleDataStore means = DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_TEMP);
// Calculate average of neighborhood for each object and perform a linear
// regression using the covariance matrix
CovarianceMatrix covm = new CovarianceMatrix(2);
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
final double local = relation.get(iditer).doubleValue(0);
// Compute mean of neighbors
Mean mean = new Mean();
DBIDs neighbors = npred.getNeighborDBIDs(iditer);
for (DBIDIter iter = neighbors.iter(); iter.valid(); iter.advance()) {
if (DBIDUtil.equal(iditer, iter)) {
continue;
}
mean.put(relation.get(iter).doubleValue(0));
}
final double m;
if (mean.getCount() > 0) {
m = mean.getMean();
} else {
// if object id has no neighbors ==> avg = non-spatial attribute of id
m = local;
}
// Store the mean for the score calculation
means.putDouble(iditer, m);
covm.put(new double[] { local, m });
}
// Finalize covariance matrix, compute linear regression
final double slope, inter;
{
double[] meanv = covm.getMeanVector();
double[][] fmat = covm.destroyToSampleMatrix();
final double covxx = fmat[0][0], covxy = fmat[0][1];
slope = covxy / covxx;
inter = meanv[1] - slope * meanv[0];
}
// calculate mean and variance for error
WritableDoubleDataStore scores = DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_STATIC);
MeanVariance mv = new MeanVariance();
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
// Compute the error from the linear regression
double y_i = relation.get(iditer).doubleValue(0);
double e = means.doubleValue(iditer) - (slope * y_i + inter);
scores.putDouble(iditer, e);
mv.put(e);
}
// Normalize scores
DoubleMinMax minmax = new DoubleMinMax();
{
final double mean = mv.getMean();
final double variance = mv.getNaiveStddev();
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
double score = Math.abs((scores.doubleValue(iditer) - mean) / variance);
minmax.put(score);
scores.putDouble(iditer, score);
}
}
// build representation
DoubleRelation scoreResult = new MaterializedDoubleRelation("SPO", "Scatterplot-Outlier", scores, relation.getDBIDs());
OutlierScoreMeta scoreMeta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 0);
OutlierResult or = new OutlierResult(scoreMeta, scoreResult);
or.addChildResult(npred);
return or;
}
use of de.lmu.ifi.dbs.elki.result.outlier.OutlierScoreMeta in project elki by elki-project.
the class CTLuMedianMultipleAttributes method run.
/**
* Run the algorithm
*
* @param database Database
* @param spatial Spatial relation
* @param attributes Attributes relation
* @return Outlier detection result
*/
public OutlierResult run(Database database, Relation<N> spatial, Relation<O> attributes) {
final int dim = RelationUtil.dimensionality(attributes);
if (LOG.isDebugging()) {
LOG.debug("Dimensionality: " + dim);
}
final NeighborSetPredicate npred = getNeighborSetPredicateFactory().instantiate(database, spatial);
CovarianceMatrix covmaker = new CovarianceMatrix(dim);
WritableDataStore<double[]> deltas = DataStoreUtil.makeStorage(attributes.getDBIDs(), DataStoreFactory.HINT_TEMP, double[].class);
for (DBIDIter iditer = attributes.iterDBIDs(); iditer.valid(); iditer.advance()) {
final O obj = attributes.get(iditer);
final DBIDs neighbors = npred.getNeighborDBIDs(iditer);
// Compute the median vector
final double[] median = new double[dim];
{
double[][] data = new double[dim][neighbors.size()];
int i = 0;
// Load data
for (DBIDIter iter = neighbors.iter(); iter.valid(); iter.advance()) {
// TODO: skip object itself within neighbors?
O nobj = attributes.get(iter);
for (int d = 0; d < dim; d++) {
data[d][i] = nobj.doubleValue(d);
}
i++;
}
for (int d = 0; d < dim; d++) {
median[d] = QuickSelect.median(data[d]);
}
}
// Delta vector "h"
double[] delta = minusEquals(obj.toArray(), median);
deltas.put(iditer, delta);
covmaker.put(delta);
}
// Finalize covariance matrix:
double[] mean = covmaker.getMeanVector();
double[][] cmati = inverse(covmaker.destroyToSampleMatrix());
DoubleMinMax minmax = new DoubleMinMax();
WritableDoubleDataStore scores = DataStoreUtil.makeDoubleStorage(attributes.getDBIDs(), DataStoreFactory.HINT_STATIC);
for (DBIDIter iditer = attributes.iterDBIDs(); iditer.valid(); iditer.advance()) {
final double score = mahalanobisDistance(cmati, deltas.get(iditer), mean);
minmax.put(score);
scores.putDouble(iditer, score);
}
DoubleRelation scoreResult = new MaterializedDoubleRelation("Median multiple attributes outlier", "median-outlier", scores, attributes.getDBIDs());
OutlierScoreMeta scoreMeta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 0);
OutlierResult or = new OutlierResult(scoreMeta, scoreResult);
or.addChildResult(npred);
return or;
}
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