/**
* Get the Meteor sufficient statistics for a test give a list of references
*
* @param test
* @param references
* @return
*/
public MeteorStats getMeteorStats(String test, ArrayList<String> references) {
// Normalize test
if (normalize) test = Normalizer.normalizeLine(test, langID, keepPunctuation);
if (lowerCase) test = test.toLowerCase();
MeteorStats stats = new MeteorStats();
stats.score = -1;
// Score each reference
for (String reference : references) {
// Normalize reference
if (normalize) reference = Normalizer.normalizeLine(reference, langID, keepPunctuation);
if (lowerCase) reference = reference.toLowerCase();
Alignment alignment = aligner.align(test, reference);
MeteorStats curStats = getMeteorStats(alignment);
if (curStats.score > stats.score) stats = curStats;
}
return stats;
}
/**
* Get the Meteor score given sufficient statistics
*
* @param stats
*/
public void computeMetrics(MeteorStats stats) {
stats.testWeightedMatches = 0;
stats.referenceWeightedMatches = 0;
stats.testWeightedLength =
(delta * (stats.testLength - stats.testFunctionWords))
+ ((1.0 - delta) * (stats.testFunctionWords));
stats.referenceWeightedLength =
(delta * (stats.referenceLength - stats.referenceFunctionWords))
+ ((1.0 - delta) * (stats.referenceFunctionWords));
// Apply module weights and delta to test and reference matches
// (Content)
for (int i = 0; i < moduleWeights.size(); i++)
stats.testWeightedMatches +=
stats.testStageMatchesContent.get(i) * moduleWeights.get(i) * delta;
for (int i = 0; i < moduleWeights.size(); i++)
stats.referenceWeightedMatches +=
stats.referenceStageMatchesContent.get(i) * moduleWeights.get(i) * delta;
// Apply module weights and delta to test and reference matches
// (Function)
for (int i = 0; i < moduleWeights.size(); i++)
stats.testWeightedMatches +=
stats.testStageMatchesFunction.get(i) * moduleWeights.get(i) * (1.0 - delta);
for (int i = 0; i < moduleWeights.size(); i++)
stats.referenceWeightedMatches +=
stats.referenceStageMatchesFunction.get(i) * moduleWeights.get(i) * (1.0 - delta);
// Precision = test matches / test length
stats.precision = stats.testWeightedMatches / stats.testWeightedLength;
// Recall = ref matches / ref length
stats.recall = stats.referenceWeightedMatches / stats.referenceWeightedLength;
// F1 = 2pr / (p + r) [not part of final score]
stats.f1 = (2 * stats.precision * stats.recall) / (stats.precision + stats.recall);
// Fmean = 1 / alpha-weighted average of p and r
stats.fMean = 1.0 / (((1.0 - alpha) / stats.precision) + (alpha / stats.recall));
// Fragmentation
double frag;
// Case if test = ref
if (stats.testTotalMatches == stats.testLength
&& stats.referenceTotalMatches == stats.referenceLength
&& stats.chunks == 1) frag = 0;
else
frag =
((double) stats.chunks)
/ (((double) (stats.testWordMatches + stats.referenceWordMatches)) / 2);
// Fragmentation penalty
stats.fragPenalty = gamma * Math.pow(frag, beta);
// Score
double score = stats.fMean * (1.0 - stats.fragPenalty);
// Catch division by zero
if (Double.isNaN(score)) stats.score = 0;
else
// score >= 0.0
stats.score = Math.max(score, 0.0);
}
/**
* Get the Meteor sufficient statistics for an alignment
*
* @param alignment
* @return
*/
public MeteorStats getMeteorStats(Alignment alignment) {
MeteorStats stats = new MeteorStats();
// Copy alignment stats
// Sum word lengths if evaluating by character
if (charBased) {
stats.testLength = 0;
for (String word : alignment.words1) stats.testLength += word.length();
stats.referenceLength = 0;
for (String word : alignment.words2) stats.referenceLength += word.length();
stats.testFunctionWords = 0;
for (int i : alignment.line1FunctionWords)
stats.testFunctionWords += alignment.words1.get(i).length();
stats.referenceFunctionWords = 0;
for (int i : alignment.line2FunctionWords)
stats.referenceFunctionWords += alignment.words2.get(i).length();
// Module and total matches with summed word lengths
int[] testStageMatchesContent = new int[alignment.moduleContentMatches1.size()];
int[] referenceStageMatchesContent = new int[alignment.moduleContentMatches1.size()];
int[] testStageMatchesFunction = new int[alignment.moduleContentMatches1.size()];
int[] referenceStageMatchesFunction = new int[alignment.moduleContentMatches1.size()];
// Sum these here to avoid pushing character-level operations to the
// aligner
for (Match m : alignment.matches) {
if (m != null) {
for (int i = 0; i < m.matchLength; i++)
if (alignment.line1FunctionWords.contains(m.matchStart + i))
testStageMatchesFunction[m.module] += alignment.words1.get(m.matchStart + i).length();
else
testStageMatchesContent[m.module] += alignment.words1.get(m.matchStart + i).length();
for (int i = 0; i < m.length; i++)
if (alignment.line2FunctionWords.contains(m.start + i))
referenceStageMatchesFunction[m.module] += alignment.words2.get(m.start + i).length();
else
referenceStageMatchesContent[m.module] += alignment.words2.get(m.start + i).length();
}
}
for (int i = 0; i < alignment.moduleContentMatches1.size(); i++) {
stats.testStageMatchesContent.add(testStageMatchesContent[i]);
stats.referenceStageMatchesContent.add(referenceStageMatchesContent[i]);
stats.testStageMatchesFunction.add(testStageMatchesFunction[i]);
stats.referenceStageMatchesFunction.add(referenceStageMatchesFunction[i]);
}
}
// Otherwise use word counts
else {
stats.testLength = alignment.words1.size();
stats.referenceLength = alignment.words2.size();
stats.testFunctionWords = alignment.line1FunctionWords.size();
stats.referenceFunctionWords = alignment.line2FunctionWords.size();
stats.testStageMatchesContent = new ArrayList<Integer>(alignment.moduleContentMatches1);
stats.referenceStageMatchesContent = new ArrayList<Integer>(alignment.moduleContentMatches2);
stats.testStageMatchesFunction = new ArrayList<Integer>(alignment.moduleFunctionMatches1);
stats.referenceStageMatchesFunction =
new ArrayList<Integer>(alignment.moduleFunctionMatches2);
}
// Same for word and character level
stats.chunks = alignment.numChunks;
// Total matches
// Important: sum from stage matches instead of taking total from
// alignment as alignment totals are WEIGHTED and totals here are
// UNWEIGHTED
for (int i = 0; i < stats.testStageMatchesContent.size(); i++) {
stats.testTotalMatches += stats.testStageMatchesContent.get(i);
stats.testTotalMatches += stats.testStageMatchesFunction.get(i);
stats.referenceTotalMatches += stats.referenceStageMatchesContent.get(i);
stats.referenceTotalMatches += stats.referenceStageMatchesFunction.get(i);
// Total for fragmentation/reporting
stats.testWordMatches += alignment.moduleContentMatches1.get(i);
stats.testWordMatches += alignment.moduleFunctionMatches1.get(i);
stats.referenceWordMatches += alignment.moduleContentMatches2.get(i);
stats.referenceWordMatches += alignment.moduleFunctionMatches2.get(i);
}
// Meteor score is required to pick best reference
computeMetrics(stats);
// Keep underlying alignment
stats.alignment = alignment;
return stats;
}