nltk StanfordNERTagger : NoClassDefFoundError: org/slf4j/LoggerFactory (In Windows)

Question

NOTE: I am using Python 2.7 as part of Anaconda distribution. I hope this is not a problem for nltk 3.1.

I am trying to use nltk for NER as

import nl         


        

Answer 1

EDITED

Note: The following answer will only work on:

• NLTK version 3.1
• Stanford Tools compiled since 2015-04-20

As both tools changes rather quickly and the API might look very different 3-6 months later. Please treat the following answer as temporal and not an eternal fix.

Always refer to https://github.com/nltk/nltk/wiki/Installing-Third-Party-Software for the latest instruction on how to interface Stanford NLP tools using NLTK!!

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Step 1

First update your NLTK to the version 3.1 using

pip install -U nltk

or (for Windows) download the latest NLTK using http://pypi.python.org/pypi/nltk

Then check that you have version 3.1 using:

python3 -c "import nltk; print(nltk.__version__)"

Step 2

Then download the zip file from http://nlp.stanford.edu/software/stanford-ner-2015-04-20.zip and unzip the file and save to C:\some\path\to\stanford-ner\ (In windows)

Step 3

Then set the environment variable for CLASSPATH to C:\some\path\to\stanford-ner\stanford-ner.jar

and the environment variable for STANFORD_MODELS to C:\some\path\to\stanford-ner\classifiers

Or in command line (ONLY for Windows):

set CLASSPATH=%CLASSPATH%;C:\some\path\to\stanford-ner\stanford-ner.jar
set STANFORD_MODELS=%STANFORD_MODELS%;C:\some\path\to\stanford-ner\classifiers

(See https://stackoverflow.com/a/17176423/610569 for click-click GUI instructions for setting environment variables in Windows)

(See Stanford Parser and NLTK for details on setting environment variables in Linux)

Step 4

Then in python:

>>> from nltk.tag import StanfordNERTagger
>>> st = StanfordNERTagger('english.all.3class.distsim.crf.ser.gz') 
>>> st.tag('Rami Eid is studying at Stony Brook University in NY'.split())
[(u'Rami', u'PERSON'), (u'Eid', u'PERSON'), (u'is', u'O'), (u'studying', u'O'), (u'at', u'O'), (u'Stony', u'ORGANIZATION'), (u'Brook', u'ORGANIZATION'), (u'University', u'ORGANIZATION'), (u'in', u'O'), (u'NY', u'O')]

Without setting the environment variables, you can try:

from nltk.tag import StanfordNERTagger

stanford_ner_dir = 'C:\\some\path\to\stanford-ner\'
eng_model_filename= stanford_ner_dir + 'classifiers\english.all.3class.distsim.crf.ser.gz'
my_path_to_jar= stanford_ner_dir + 'stanford-ner.jar'

st = StanfordNERTagger(model_filename=eng_model_filename, path_to_jar=my_path_to_jar) 
st.tag('Rami Eid is studying at Stony Brook University in NY'.split())

See more detailed instructions on Stanford Parser and NLTK