nltk.translate.metrics

module documentation
(source)

Undocumented

Function alignment_error_rate Return the Alignment Error Rate (AER) of an alignment with respect to a "gold standard" reference alignment. Return an error rate between 0.0 (perfect alignment) and 1.0 (no alignment).
def alignment_error_rate(reference, hypothesis, possible=None): (source) ΒΆ

Return the Alignment Error Rate (AER) of an alignment with respect to a "gold standard" reference alignment. Return an error rate between 0.0 (perfect alignment) and 1.0 (no alignment).

>>> from nltk.translate import Alignment
>>> ref = Alignment([(0, 0), (1, 1), (2, 2)])
>>> test = Alignment([(0, 0), (1, 2), (2, 1)])
>>> alignment_error_rate(ref, test) # doctest: +ELLIPSIS
0.6666666666666667
Parameters
reference:AlignmentA gold standard alignment (sure alignments)
hypothesis:AlignmentA hypothesis alignment (aka. candidate alignments)
possible:Alignment or NoneA gold standard reference of possible alignments (defaults to reference if None)
Returns
float or NoneUndocumented