/**
* Subroutine used by both compare methods for counting statistics from atoms stored in result
* database
*
* @param p Predicate to compare against baseline database
*/
private void countResultDBStats(Predicate p) {
tp = 0;
fn = 0;
tn = 0;
fp = 0;
errors = new HashMap<GroundAtom, Double>();
correctAtoms = new HashSet<GroundAtom>();
GroundAtom resultAtom, baselineAtom;
GroundTerm[] args;
boolean actual, expected;
Iterator<GroundAtom> iter = resultFilter.filter(Queries.getAllAtoms(result, p).iterator());
while (iter.hasNext()) {
resultAtom = iter.next();
args = new GroundTerm[resultAtom.getArity()];
for (int i = 0; i < args.length; i++) args[i] = (GroundTerm) resultAtom.getArguments()[i];
baselineAtom = baseline.getAtom(resultAtom.getPredicate(), args);
if (baselineAtom instanceof ObservedAtom) {
actual = (resultAtom.getValue() >= threshold);
expected = (baselineAtom.getValue() >= threshold);
if (actual && expected || !actual && !expected) {
// True negative
if (!actual) tn++;
// True positive
else tp++;
correctAtoms.add(resultAtom);
}
// False negative
else if (!actual) {
fn++;
errors.put(resultAtom, -1.0);
}
// False positive
else {
fp++;
errors.put(resultAtom, 1.0);
}
}
}
}
/**
* Compares the baseline with the inferred result for a given predicate. Checks the baseline
* database for atoms
*
* @param Predicate p : The predicate to compare
* @param int maxAtoms : Defines the maximum number of base atoms that can be found for the given
* predicate. (This will vary, depending on the predicate and the problem.)
*/
@Override
public DiscretePredictionStatistics compare(Predicate p, int maxBaseAtoms) {
countResultDBStats(p);
Iterator<GroundAtom> res = resultFilter.filter(Queries.getAllAtoms(baseline, p).iterator());
double expected;
while (res.hasNext()) {
GroundAtom baselineAtom = res.next();
if (!errors.containsKey(baselineAtom) && !correctAtoms.contains(baselineAtom)) {
// Missed result
expected = (baselineAtom.getValue() >= threshold) ? 1.0 : 0.0;
if (expected != 0.0) {
errors.put(
result.getAtom(baselineAtom.getPredicate(), baselineAtom.getArguments()), expected);
fn++;
}
}
}
tn = maxBaseAtoms - tp - fp - fn;
return new DiscretePredictionStatistics(tp, fp, tn, fn, threshold, errors, correctAtoms);
}