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Questions tagged [named-entity-recognition]

Named-entity recognition (NER) (also known as entity identification and entity extraction) is a subtask of information extraction that seeks to locate and classify atomic elements in text into predefined categories such as the names of persons, organizations, locations, expressions of times, quantities, monetary values, percentages, etc.

Named-entity recognition (NER) (also known as entity identification and entity extraction) is a subtask of information extraction that seeks to locate and classify atomic elements in text into predefined categories such as the names of persons, organizations, locations, expressions of times, quantities, monetary values, percentages, etc.

Most research on NER systems has been structured as taking an unannotated block of text, such as this one:

Jim bought 300 shares of Acme Corp. in 2006.

And producing an annotated block of text that highlights where the named entities are, such as this one:

<ENAMEX TYPE="PERSON">Jim</ENAMEX>bought<NUMEX TYPE="QUANTITY">300</NUMEX>shares of<ENAMEX TYPE="ORGANIZATION">Acme Corp.</ENAMEX> in <TIMEX TYPE="DATE">2006</TIMEX>.

In this example, the annotations are marked using XML ENAMEX elements, following the format developed for the Message Understanding Conference in the 1990s.

State-of-the-art NER systems for English produce near-human performance. For example, the best system entering MUC-7 scored 93.39% of F-measure while human annotators scored 97.60% and 96.95%.

Source:http://en.wikipedia.org/wiki/Named-entity_recognition

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How does Apple find dates, times and addresses in emails?

In the iOS email client, when an email contains a date, time or location, the text becomes a hyperlink and it is possible to create an appointment or look at a map simply by tapping the link. It not only works for emails in English, but in other…
Martin
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What do the BILOU tags mean in Named Entity Recognition?

Title pretty much sums up the question. I've noticed that in some papers people have referred to a BILOU encoding scheme for NER as opposed to the typical BIO tagging scheme (Such as this paper by Ratinov and Roth in 2009…
GrantD71
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NLTK Named Entity Recognition with Custom Data

I'm trying to extract named entities from my text using NLTK. I find that NLTK NER is not very accurate for my purpose and I want to add some more tags of my own as well. I've been trying to find a way to train my own NER, but I don't seem to be…
user1502248
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Is it possible to train Stanford NER system to recognize more named entities types?

I'm using some NLP libraries now, (stanford and nltk) Stanford I saw the demo part but just want to ask if it possible to use it to identify more entity types. So currently stanford NER system (as the demo shows) can recognize entities as…
JudyJiang
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NLTK for Named Entity Recognition

I am trying to use NLTK toolkit to get extract place, date and time from text messages. I just installed the toolkit on my machine and I wrote this quick snippet to test it out: sentence = "Let's meet tomorrow at 9 pm"; tokens =…
Darth.Vader
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Named Entity Recognition Libraries for Java

I am looking for a simple but "good enough" Named Entity Recognition library (and dictionary) for java, I am looking to process emails and documents and extract some "basic information" like: Names, places, Address and Dates I've been looking…
webclimber
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Extract list of Persons and Organizations using Stanford NER Tagger in NLTK

I am trying to extract list of persons and organizations using Stanford Named Entity Recognizer (NER) in Python NLTK. When I run: from nltk.tag.stanford import NERTagger st =…
user1680859
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Algorithms for named entity recognition

I would like to use named entity recognition (NER) to find adequate tags for texts in a database. I know there is a Wikipedia article about this and lots of other pages describing NER, I would preferably hear something about this topic from…
caw
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Training n-gram NER with Stanford NLP

Recently I have been trying to train n-gram entities with Stanford Core NLP. I have followed the following tutorials - http://nlp.stanford.edu/software/crf-faq.shtml#b With this, I am able to specify only unigram tokens and the class it belongs to.…
Arun A K
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Named Entity Recognition for NLTK in Python. Identifying the NE

I need to classify words into their parts of speech. Like a verb, a noun, an adverb etc.. I used the nltk.word_tokenize() #to identify word in a sentence nltk.pos_tag() #to identify the parts of speech nltk.ne_chunk() #to identify Named…
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NLTK Named Entity recognition to a Python list

I used NLTK's ne_chunk to extract named entities from a text: my_sent = "WASHINGTON -- In the wake of a string of abuses by New York police officers in the 1990s, Loretta E. Lynch, the top federal prosecutor in Brooklyn, spoke forcefully about the…
Zlo
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Multi-term named entities in Stanford Named Entity Recognizer

I'm using the Stanford Named Entity Recognizer http://nlp.stanford.edu/software/CRF-NER.shtml and it's working fine. This is List> out = classifier.classify(text); for (List sentence : out) { for (CoreLabel…
Krt_Malta
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How to create a good NER training model in OpenNLP?

I just have started with OpenNLP. I need to create a simple training model to recognize name entities. Reading the doc here https://opennlp.apache.org/docs/1.8.0/apidocs/opennlp-tools/opennlp/tools/namefind I see this simple text to train the…
Dail
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spaCy NER probability

I want to combine spaCy's NER engine with a separate NER engine (a BoW model). I'm currently comparing outputs from the two engines, trying to figure out what the optimal combination of the two would be. Both perform decently, but quite often spaCy…
Mede
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How does spacy use word embeddings for Named Entity Recognition (NER)?

I'm trying to train an NER model using spaCy to identify locations, (person) names, and organisations. I'm trying to understand how spaCy recognises entities in text and I've not been able to find an answer. From this issue on Github and this…
Navaneethan Santhanam
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