/**
* Main loop for OUTRES
*
* @param relation Relation to process
* @return Outlier detection result
*/
public OutlierResult run(Relation<V> relation) {
WritableDoubleDataStore ranks =
DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_STATIC);
DoubleMinMax minmax = new DoubleMinMax();
KernelDensityEstimator kernel = new KernelDensityEstimator(relation);
long[] subspace = BitsUtil.zero(kernel.dim);
FiniteProgress progress =
LOG.isVerbose() ? new FiniteProgress("OUTRES scores", relation.size(), LOG) : null;
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
BitsUtil.zeroI(subspace);
double score = outresScore(0, subspace, iditer, kernel);
ranks.putDouble(iditer, score);
minmax.put(score);
LOG.incrementProcessed(progress);
}
LOG.ensureCompleted(progress);
OutlierScoreMeta meta =
new InvertedOutlierScoreMeta(minmax.getMin(), minmax.getMax(), 0., 1., 1.);
OutlierResult outresResult =
new OutlierResult(
meta,
new MaterializedDoubleRelation("OUTRES", "outres-score", ranks, relation.getDBIDs()));
return outresResult;
}
/**
* The main run method
*
* @param database Database to use (actually unused)
* @param spatial Relation for neighborhood
* @param relation Attributes to evaluate
* @return Outlier result
*/
public OutlierResult run(Database database, Relation<N> spatial, Relation<O> relation) {
final NeighborSetPredicate npred =
getNeighborSetPredicateFactory().instantiate(database, spatial);
DistanceQuery<O> distFunc = getNonSpatialDistanceFunction().instantiate(relation);
WritableDoubleDataStore lrds =
DataStoreUtil.makeDoubleStorage(
relation.getDBIDs(), DataStoreFactory.HINT_TEMP | DataStoreFactory.HINT_HOT);
WritableDoubleDataStore lofs =
DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_STATIC);
DoubleMinMax lofminmax = new DoubleMinMax();
// Compute densities
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
DBIDs neighbors = npred.getNeighborDBIDs(iditer);
double avg = 0;
for (DBIDIter iter = neighbors.iter(); iter.valid(); iter.advance()) {
avg += distFunc.distance(iditer, iter);
}
double lrd = 1 / (avg / neighbors.size());
if (Double.isNaN(lrd)) {
lrd = 0;
}
lrds.putDouble(iditer, lrd);
}
// Compute density quotients
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
DBIDs neighbors = npred.getNeighborDBIDs(iditer);
double avg = 0;
for (DBIDIter iter = neighbors.iter(); iter.valid(); iter.advance()) {
avg += lrds.doubleValue(iter);
}
final double lrd = (avg / neighbors.size()) / lrds.doubleValue(iditer);
if (!Double.isNaN(lrd)) {
lofs.putDouble(iditer, lrd);
lofminmax.put(lrd);
} else {
lofs.putDouble(iditer, 0.0);
}
}
// Build result representation.
DoubleRelation scoreResult =
new MaterializedDoubleRelation(
"Spatial Outlier Factor", "sof-outlier", lofs, relation.getDBIDs());
OutlierScoreMeta scoreMeta =
new QuotientOutlierScoreMeta(
lofminmax.getMin(), lofminmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 1.0);
OutlierResult or = new OutlierResult(scoreMeta, scoreResult);
or.addChildResult(npred);
return or;
}
/**
* Run the algorithm on the given relation.
*
* @param database Database
* @param relation Relation to process
* @return Outlier result
*/
public OutlierResult run(Database database, Relation<? extends NumberVector> relation) {
@SuppressWarnings("unchecked")
PrimitiveDistanceQuery<? super NumberVector> distq =
(PrimitiveDistanceQuery<? super NumberVector>)
database.getDistanceQuery(relation, distanceFunction);
Collection<? extends NumberVector> refPoints = refp.getReferencePoints(relation);
if (refPoints.size() < 1) {
throw new AbortException("Cannot compute ROS without reference points!");
}
DBIDs ids = relation.getDBIDs();
if (k >= ids.size()) {
throw new AbortException("k must not be chosen larger than the database size!");
}
// storage of distance/score values.
WritableDoubleDataStore rbod_score =
DataStoreUtil.makeDoubleStorage(
ids, DataStoreFactory.HINT_STATIC | DataStoreFactory.HINT_HOT, Double.NaN);
// Compute density estimation:
for (NumberVector refPoint : refPoints) {
DoubleDBIDList referenceDists = computeDistanceVector(refPoint, relation, distq);
updateDensities(rbod_score, referenceDists);
}
// compute maximum density
DoubleMinMax mm = new DoubleMinMax();
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
mm.put(rbod_score.doubleValue(iditer));
}
// compute ROS
double scale = mm.getMax() > 0. ? 1. / mm.getMax() : 1.;
mm.reset(); // Reuse
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
double score = 1 - (rbod_score.doubleValue(iditer) * scale);
mm.put(score);
rbod_score.putDouble(iditer, score);
}
DoubleRelation scoreResult =
new MaterializedDoubleRelation(
"Reference-points Outlier Scores",
"reference-outlier",
rbod_score,
relation.getDBIDs());
OutlierScoreMeta scoreMeta = new BasicOutlierScoreMeta(mm.getMin(), mm.getMax(), 0., 1., 0.);
OutlierResult result = new OutlierResult(scoreMeta, scoreResult);
// adds reference points to the result. header information for the
// visualizer to find the reference points in the result
result.addChildResult(
new ReferencePointsResult<>("Reference points", "reference-points", refPoints));
return result;
}
/**
* Run the algorithm
*
* @param relation Data relation
* @return Outlier result
*/
public OutlierResult run(Relation<V> relation) {
DoubleMinMax mm = new DoubleMinMax();
// resulting scores
WritableDoubleDataStore oscores =
DataStoreUtil.makeDoubleStorage(
relation.getDBIDs(), DataStoreFactory.HINT_TEMP | DataStoreFactory.HINT_HOT);
// Compute mean and covariance Matrix
CovarianceMatrix temp = CovarianceMatrix.make(relation);
double[] mean = temp.getMeanVector(relation).toArray();
// debugFine(mean.toString());
Matrix covarianceMatrix = temp.destroyToNaiveMatrix();
// debugFine(covarianceMatrix.toString());
Matrix covarianceTransposed =
covarianceMatrix.cheatToAvoidSingularity(SINGULARITY_CHEAT).inverse();
// Normalization factors for Gaussian PDF
final double fakt =
(1.0
/ (Math.sqrt(
MathUtil.powi(MathUtil.TWOPI, RelationUtil.dimensionality(relation))
* covarianceMatrix.det())));
// for each object compute Mahalanobis distance
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
double[] x = minusEquals(relation.get(iditer).toArray(), mean);
// Gaussian PDF
final double mDist = transposeTimesTimes(x, covarianceTransposed, x);
final double prob = fakt * Math.exp(-mDist * .5);
mm.put(prob);
oscores.putDouble(iditer, prob);
}
final OutlierScoreMeta meta;
if (invert) {
double max = mm.getMax() != 0 ? mm.getMax() : 1.;
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
oscores.putDouble(iditer, (max - oscores.doubleValue(iditer)) / max);
}
meta = new BasicOutlierScoreMeta(0.0, 1.0);
} else {
meta = new InvertedOutlierScoreMeta(mm.getMin(), mm.getMax(), 0.0, Double.POSITIVE_INFINITY);
}
DoubleRelation res =
new MaterializedDoubleRelation(
"Gaussian Model Outlier Score", "gaussian-model-outlier", oscores, relation.getDBIDs());
return new OutlierResult(meta, res);
}
@Override
public CanvasSize estimateViewport() {
if (viewport == null) {
final int dim = proj.getDimensionality();
DoubleMinMax minmaxx = new DoubleMinMax();
DoubleMinMax minmaxy = new DoubleMinMax();
// Origin
final double[] vec = new double[dim];
double[] orig = projectScaledToRender(vec);
minmaxx.put(orig[0]);
minmaxy.put(orig[1]);
// Diagonal point
Arrays.fill(vec, 1.);
double[] diag = projectScaledToRender(vec);
minmaxx.put(diag[0]);
minmaxy.put(diag[1]);
// Axis end points
for (int d = 0; d < dim; d++) {
Arrays.fill(vec, 0.);
vec[d] = 1.;
double[] ax = projectScaledToRender(vec);
minmaxx.put(ax[0]);
minmaxy.put(ax[1]);
}
viewport =
new CanvasSize(minmaxx.getMin(), minmaxx.getMax(), minmaxy.getMin(), minmaxy.getMax());
}
return viewport;
}
/**
* Run the algorithm
*
* @param database Database to process
* @param relation Relation to process
* @return Outlier result
*/
public OutlierResult run(Database database, Relation<O> relation) {
DistanceQuery<O> distFunc = database.getDistanceQuery(relation, getDistanceFunction());
RangeQuery<O> rangeQuery = database.getRangeQuery(distFunc);
DBIDs ids = relation.getDBIDs();
// LOCI preprocessing step
WritableDataStore<DoubleIntArrayList> interestingDistances =
DataStoreUtil.makeStorage(
relation.getDBIDs(),
DataStoreFactory.HINT_TEMP | DataStoreFactory.HINT_SORTED,
DoubleIntArrayList.class);
precomputeInterestingRadii(ids, rangeQuery, interestingDistances);
// LOCI main step
FiniteProgress progressLOCI =
LOG.isVerbose() ? new FiniteProgress("LOCI scores", relation.size(), LOG) : null;
WritableDoubleDataStore mdef_norm =
DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_STATIC);
WritableDoubleDataStore mdef_radius =
DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_STATIC);
DoubleMinMax minmax = new DoubleMinMax();
// Shared instance, to save allocations.
MeanVariance mv_n_r_alpha = new MeanVariance();
for (DBIDIter iditer = ids.iter(); iditer.valid(); iditer.advance()) {
final DoubleIntArrayList cdist = interestingDistances.get(iditer);
final double maxdist = cdist.getDouble(cdist.size() - 1);
final int maxneig = cdist.getInt(cdist.size() - 1);
double maxmdefnorm = 0.0;
double maxnormr = 0;
if (maxneig >= nmin) {
// Compute the largest neighborhood we will need.
DoubleDBIDList maxneighbors = rangeQuery.getRangeForDBID(iditer, maxdist);
// TODO: Ensure the result is sorted. This is currently implied.
// For any critical distance, compute the normalized MDEF score.
for (int i = 0, size = cdist.size(); i < size; i++) {
// Only start when minimum size is fulfilled
if (cdist.getInt(i) < nmin) {
continue;
}
final double r = cdist.getDouble(i);
final double alpha_r = alpha * r;
// compute n(p_i, \alpha * r) from list (note: alpha_r is not cdist!)
final int n_alphar = cdist.getInt(cdist.find(alpha_r));
// compute \hat{n}(p_i, r, \alpha) and the corresponding \simga_{MDEF}
mv_n_r_alpha.reset();
for (DoubleDBIDListIter neighbor = maxneighbors.iter();
neighbor.valid();
neighbor.advance()) {
// Stop at radius r
if (neighbor.doubleValue() > r) {
break;
}
DoubleIntArrayList cdist2 = interestingDistances.get(neighbor);
int rn_alphar = cdist2.getInt(cdist2.find(alpha_r));
mv_n_r_alpha.put(rn_alphar);
}
// We only use the average and standard deviation
final double nhat_r_alpha = mv_n_r_alpha.getMean();
final double sigma_nhat_r_alpha = mv_n_r_alpha.getNaiveStddev();
// Redundant divisions by nhat_r_alpha removed.
final double mdef = nhat_r_alpha - n_alphar;
final double sigmamdef = sigma_nhat_r_alpha;
final double mdefnorm = mdef / sigmamdef;
if (mdefnorm > maxmdefnorm) {
maxmdefnorm = mdefnorm;
maxnormr = r;
}
}
} else {
// FIXME: when nmin was not fulfilled - what is the proper value then?
maxmdefnorm = Double.POSITIVE_INFINITY;
maxnormr = maxdist;
}
mdef_norm.putDouble(iditer, maxmdefnorm);
mdef_radius.putDouble(iditer, maxnormr);
minmax.put(maxmdefnorm);
LOG.incrementProcessed(progressLOCI);
}
LOG.ensureCompleted(progressLOCI);
DoubleRelation scoreResult =
new MaterializedDoubleRelation(
"LOCI normalized MDEF", "loci-mdef-outlier", mdef_norm, relation.getDBIDs());
OutlierScoreMeta scoreMeta =
new QuotientOutlierScoreMeta(
minmax.getMin(), minmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 0.0);
OutlierResult result = new OutlierResult(scoreMeta, scoreResult);
result.addChildResult(
new MaterializedDoubleRelation(
"LOCI MDEF Radius", "loci-critical-radius", mdef_radius, relation.getDBIDs()));
return result;
}
/**
* Run the algorithm.
*
* @param database Database to use
* @param relation Relation to use
* @return Result
*/
public OutlierResult run(Database database, Relation<?> relation) {
WritableDoubleDataStore scores =
DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_STATIC);
DoubleMinMax minmax = new DoubleMinMax();
try (InputStream in = FileUtil.tryGzipInput(new FileInputStream(file)); //
TokenizedReader reader = CSVReaderFormat.DEFAULT_FORMAT.makeReader()) {
Tokenizer tokenizer = reader.getTokenizer();
CharSequence buf = reader.getBuffer();
Matcher mi = idpattern.matcher(buf), ms = scorepattern.matcher(buf);
reader.reset(in);
while (reader.nextLineExceptComments()) {
Integer id = null;
double score = Double.NaN;
for (
/* initialized by nextLineExceptComments */ ; tokenizer.valid(); tokenizer.advance()) {
mi.region(tokenizer.getStart(), tokenizer.getEnd());
ms.region(tokenizer.getStart(), tokenizer.getEnd());
final boolean mif = mi.find();
final boolean msf = ms.find();
if (mif && msf) {
throw new AbortException(
"ID pattern and score pattern both match value: " + tokenizer.getSubstring());
}
if (mif) {
if (id != null) {
throw new AbortException(
"ID pattern matched twice: previous value "
+ id
+ " second value: "
+ tokenizer.getSubstring());
}
id = Integer.parseInt(buf.subSequence(mi.end(), tokenizer.getEnd()).toString());
}
if (msf) {
if (!Double.isNaN(score)) {
throw new AbortException(
"Score pattern matched twice: previous value "
+ score
+ " second value: "
+ tokenizer.getSubstring());
}
score = ParseUtil.parseDouble(buf, ms.end(), tokenizer.getEnd());
}
}
if (id != null && !Double.isNaN(score)) {
scores.putDouble(DBIDUtil.importInteger(id), score);
minmax.put(score);
} else if (id == null && Double.isNaN(score)) {
LOG.warning(
"Line did not match either ID nor score nor comment: " + reader.getLineNumber());
} else {
throw new AbortException(
"Line matched only ID or only SCORE patterns: " + reader.getLineNumber());
}
}
} catch (IOException e) {
throw new AbortException(
"Could not load outlier scores: " + e.getMessage() + " when loading " + file, e);
}
OutlierScoreMeta meta;
if (inverted) {
meta = new InvertedOutlierScoreMeta(minmax.getMin(), minmax.getMax());
} else {
meta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax());
}
DoubleRelation scoresult =
new MaterializedDoubleRelation(
"External Outlier", "external-outlier", scores, relation.getDBIDs());
OutlierResult or = new OutlierResult(meta, scoresult);
// Apply scaling
if (scaling instanceof OutlierScalingFunction) {
((OutlierScalingFunction) scaling).prepare(or);
}
DoubleMinMax mm = new DoubleMinMax();
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
double val = scoresult.doubleValue(iditer);
val = scaling.getScaled(val);
scores.putDouble(iditer, val);
mm.put(val);
}
meta = new BasicOutlierScoreMeta(mm.getMin(), mm.getMax());
or = new OutlierResult(meta, scoresult);
return or;
}
