'Given a correctly chunked sentence, score another chunked
version of the same sentence.
:type correct: chunk structure
:param correct: The known-correct ("gold standard") chunked
sentence.
:type guessed: chunk structure
:param guessed: The chunked sentence to be scored.'

def score(self, correct, guessed):

    self._correct |= _chunksets(correct, self._count, self._chunk_label)
    self._guessed |= _chunksets(guessed, self._count, self._chunk_label)
    self._count += 1
    self._measuresNeedUpdate = True
    try:
        correct_tags = tree2conlltags(correct)
        guessed_tags = tree2conlltags(guessed)
    except ValueError:
        correct_tags = guessed_tags = ()
    self._tags_total += len(correct_tags)
    self._tags_correct += sum((1 for (t, g) in zip(guessed_tags, correct_tags) if (t == g)))
