What Is The Accuracy Of Nltk Pos_tagger?

I'm writing a dissertation, and using nltk.pos_tagger in my work. I can't find any information about what the accuracy of this algorithm. Does anybody know where can I find such in

Solution 1:

NLTK default pos tagger pos_tag is a MaxEnt tagger, see line 82 from https://github.com/nltk/nltk/blob/develop/nltk/tag/init.py

from nltk.corpus import brown
from nltk.data import load

sents = brown.tagged_sents()
# test on last 10% of brown corpus.
numtest = len(sents) / 10
testsents = sents[numtest:]

_POS_TAGGER = 'taggers/maxent_treebank_pos_tagger/english.pickle'

tagger = load(_POS_TAGGER)

print tagger.evaluate(testsents)

[out]: