예제 #1
0
  @Override
  public ClassScore computeScore(Description description) {

    // TODO: reuse code to ensure that we never return inconsistent results
    // between getAccuracy, getAccuracyOrTooWeak and computeScore

    // overhang
    Set<Individual> additionalInstances = new TreeSet<Individual>();
    for (Individual ind : superClassInstances) {
      if (getReasoner().hasType(description, ind)) {
        additionalInstances.add(ind);
      }
    }

    // coverage
    Set<Individual> coveredInstances = new TreeSet<Individual>();
    for (Individual ind : classInstances) {
      if (getReasoner().hasType(description, ind)) {
        coveredInstances.add(ind);
      }
    }

    double recall = coveredInstances.size() / (double) classInstances.size();
    double precision =
        (additionalInstances.size() + coveredInstances.size() == 0)
            ? 0
            : coveredInstances.size()
                / (double) (coveredInstances.size() + additionalInstances.size());
    // for each description with less than 100% coverage, we check whether it is
    // leads to an inconsistent knowledge base

    double acc = 0;
    if (heuristic.equals(HeuristicType.FMEASURE)) {
      acc = getFMeasure(recall, precision);
    } else if (heuristic.equals(HeuristicType.AMEASURE)) {
      acc = Heuristics.getAScore(recall, precision, coverageFactor);
    } else {
      // TODO: some superfluous instance checks are required to compute accuracy =>
      // move accuracy computation here if possible
      acc = getAccuracyOrTooWeakExact(description, 1);
    }

    if (checkConsistency) {

      // we check whether the axiom already follows from the knowledge base
      //			boolean followsFromKB = reasoner.isSuperClassOf(description, classToDescribe);

      //			boolean followsFromKB = equivalence ? reasoner.isEquivalentClass(description,
      // classToDescribe) : reasoner.isSuperClassOf(description, classToDescribe);
      boolean followsFromKB = followsFromKB(description);

      // workaround due to a bug (see
      // http://sourceforge.net/tracker/?func=detail&aid=2866610&group_id=203619&atid=986319)
      //			boolean isConsistent = coverage >= 0.999999 || isConsistent(description);
      // (if the axiom follows, then the knowledge base remains consistent)
      boolean isConsistent = followsFromKB || isConsistent(description);

      //			double acc = useFMeasure ? getFMeasure(coverage, protusion) : getAccuracy(coverage,
      // protusion);
      return new ClassScore(
          coveredInstances,
          Helper.difference(classInstancesSet, coveredInstances),
          recall,
          additionalInstances,
          precision,
          acc,
          isConsistent,
          followsFromKB);

    } else {
      return new ClassScore(
          coveredInstances,
          Helper.difference(classInstancesSet, coveredInstances),
          recall,
          additionalInstances,
          precision,
          acc);
    }
  }
예제 #2
0
  @Override
  public ClassScore computeScore(OWLClassExpression description, double noise) {

    // TODO: reuse code to ensure that we never return inconsistent results
    // between getAccuracy, getAccuracyOrTooWeak and computeScore
    Set<OWLIndividual> additionalInstances = new TreeSet<OWLIndividual>();
    Set<OWLIndividual> coveredInstances = new TreeSet<OWLIndividual>();

    int additionalInstancesCnt = 0;
    int coveredInstancesCnt = 0;

    if (reasoner.getClass().isAssignableFrom(SPARQLReasoner.class)) {
      // R(C)
      String query =
          "SELECT (COUNT(DISTINCT(?s)) AS ?cnt) WHERE {"
              + "?s a ?sup . ?classToDescribe <http://www.w3.org/2000/01/rdf-schema#subClassOf> ?sup . "
              + converter.convert("?s", description)
              + "FILTER NOT EXISTS {?s a ?classToDescribe}}";
      ParameterizedSparqlString template = new ParameterizedSparqlString(query);
      // System.err.println(converter.convert("?s", description));
      // template.setIri("cls", description.asOWLClass().toStringID());
      template.setIri("classToDescribe", classToDescribe.toStringID());

      QueryExecution qe =
          ((SPARQLReasoner) reasoner)
              .getQueryExecutionFactory()
              .createQueryExecution(template.toString());
      additionalInstancesCnt = qe.execSelect().next().getLiteral("cnt").getInt();

      // R(A)
      OWLObjectIntersectionOf ce = df.getOWLObjectIntersectionOf(classToDescribe, description);
      coveredInstancesCnt = ((SPARQLReasoner) reasoner).getPopularityOf(ce);
    } else {
      // overhang
      for (OWLIndividual ind : superClassInstances) {
        if (getReasoner().hasType(description, ind)) {
          additionalInstances.add(ind);
        }
      }

      // coverage
      for (OWLIndividual ind : classInstances) {
        if (getReasoner().hasType(description, ind)) {
          coveredInstances.add(ind);
        }
      }
      additionalInstancesCnt = additionalInstances.size();
      coveredInstancesCnt = coveredInstances.size();
    }

    double recall = coveredInstancesCnt / (double) classInstances.size();
    double precision =
        (additionalInstancesCnt + coveredInstancesCnt == 0)
            ? 0
            : coveredInstancesCnt / (double) (coveredInstancesCnt + additionalInstancesCnt);
    // for each OWLClassExpression with less than 100% coverage, we check whether it is
    // leads to an inconsistent knowledge base

    double acc = 0;
    if (heuristic.equals(HeuristicType.FMEASURE)) {
      acc = Heuristics.getFScore(recall, precision, coverageFactor);
    } else if (heuristic.equals(HeuristicType.AMEASURE)) {
      acc = Heuristics.getAScore(recall, precision, coverageFactor);
    } else {
      // TODO: some superfluous instance checks are required to compute accuracy =>
      // move accuracy computation here if possible
      acc = getAccuracyOrTooWeakExact(description, noise);
    }

    if (checkConsistency) {

      // we check whether the axiom already follows from the knowledge base
      //			boolean followsFromKB = reasoner.isSuperClassOf(description, classToDescribe);

      //			boolean followsFromKB = equivalence ? reasoner.isEquivalentClass(description,
      // classToDescribe) : reasoner.isSuperClassOf(description, classToDescribe);
      boolean followsFromKB = followsFromKB(description);

      // workaround due to a bug (see
      // http://sourceforge.net/tracker/?func=detail&aid=2866610&group_id=203619&atid=986319)
      //			boolean isConsistent = coverage >= 0.999999 || isConsistent(description);
      // (if the axiom follows, then the knowledge base remains consistent)
      boolean isConsistent = followsFromKB || isConsistent(description);

      //			double acc = useFMeasure ? getFMeasure(coverage, protusion) : getAccuracy(coverage,
      // protusion);
      return new ClassScore(
          coveredInstances,
          Helper.difference(classInstancesSet, coveredInstances),
          recall,
          additionalInstances,
          precision,
          acc,
          isConsistent,
          followsFromKB);

    } else {
      return new ClassScore(
          coveredInstances,
          Helper.difference(classInstancesSet, coveredInstances),
          recall,
          additionalInstances,
          precision,
          acc);
    }
  }