Word Embedding¶
Gluon NLP makes it easy to evaluate and train word embeddings. Here are examples to evaluate the pre-trained embeddings included in the Gluon NLP toolkit as well as example scripts for training embeddings on custom datasets.
Word Embedding Evaluation¶
To evaluate a specific embedding on one or multiple datasets you can use the included evaluate_pretrained.py as follows.
$ python evaluate_pretrained.py
Call the script with the –help option to get an overview of the supported options. We include a run_all.sh script to run the evaluation for the pre-trained English Glove and fastText embeddings included in GluonNLP.
$ run_all.sh
The resulting logs and a notebook containing a ranking for the different evaluation tasks are available here.
Word Embedding Training (Skipgram and CBOW)¶
Besides loading pre-trained embeddings, the Gluon NLP toolkit also makes it easy to train embeddings.
The following code block shows how to use Gluon NLP to train a SkipGram or CBOW models. The script and parts of the Gluon NLP library support just-in-time compilation with numba, which is enabled automatically when numba is installed on the system. Please pip install –upgrade numba to make sure training speed is not needlessly throttled by Python.
$ python train_sg_cbow.py --model skipgram --ngram-buckets 0 # Word2Vec Skipgram
$ python train_sg_cbow.py --model skipgram --ngram-buckets 2000000 # fastText Skipgram
$ python train_sg_cbow.py --model cbow --ngram-buckets 0 # Word2Vec CBOW
$ python train_sg_cbow.py --model cbow --ngram-buckets 2000000 # fastText CBOW
Word2Vec models were introduced by Mikolov et al., “Efficient estimation of word representations in vector space” ICLR Workshop 2013. FastText models were introudced by Bojanowski et al., “Enriching word vectors with subword information” TACL 2017.
We report the results obtained by running the python3
train_sg_cbow.py --batch-size 4096 --epochs 5 --data fil9 --model skipgram
script.For comparison we also report the results obtained by training FastText
with the facebookresearch/fastText implementation. All results are obtained by
training 5 epochs on the Fil9
dataset.
Similarity Dataset |
facebookresearch/fastText |
train_sg_cbow.py |
|---|---|---|
WordSim353-similarity |
0.752 |
0.734 |
WordSim353-relatedness |
0.612 |
0.608 |
MEN (test set) |
0.736 |
0.700 |
RadinskyMTurk |
0.687 |
0.655 |
RareWords |
0.420 |
0.457 |
SimLex999 |
0.320 |
0.346 |
SimVerb3500 |
0.190 |
0.235 |
SemEval17Task2 (test set) |
0.541 |
0.542 |
BakerVerb143 |
0.406 |
0.383 |
YangPowersVerb130 |
0.489 |
0.466 |
Google Analogy Dataset |
facebookresearch/fastText |
train_sg_cbow.py |
|---|---|---|
capital-common-countries |
0.796 |
0.581 |
capital-world |
0.442 |
0.334 |
currency |
0.068 |
0.074 |
city-in-state |
0.198 |
0.076 |
family |
0.498 |
0.593 |
gram1-adjective-to-adverb |
0.377 |
0.688 |
gram2-opposite |
0.343 |
0.693 |
gram3-comparative |
0.646 |
0.868 |
gram4-superlative |
0.510 |
0.757 |
gram5-present-participle |
0.445 |
0.792 |
gram6-nationality-adjective |
0.828 |
0.840 |
gram7-past-tense |
0.385 |
0.380 |
gram8-plural |
0.706 |
0.810 |
gram9-plural-verbs |
0.501 |
0.813 |
Loading of fastText models with subword information¶
Fasttext models trained with the library of facebookresearch are exported both in a text and a binary format. Unlike the text format, the binary format preserves information about subword units and consequently supports computation of word vectors for words unknown during training (and not included in the text format). Besides training new fastText embeddings with Gluon NLP it is also possible to load the binary format into a Block provided by the Gluon NLP toolkit using FasttextEmbeddingModel.load_fasttext_format.
Word Embedding Training (GloVe)¶
Gluon NLP also supports training GloVe models.
$ python train_glove.py tools/build/cooccurrences.npz tools/build/vocab.txt
Where the cooccurrences.npz is a numpy archive containing the sparse word-word cooccurrence matrix and vocab.txt a textfile containing the words and their counts. They can be constructed from a text corpus using the included vocab_count and cooccur tools. They can be used as follows
$ mkdir tools/build; cd tools/build; cmake ..; make
$ ./vocab_count corpus-part1.txt corpus-part2.txt > vocab.txt
$ ./cooccur corpus-part1.txt corpus-part2.txt < vocab.txt
Also see ./vocab_count –help and ./cooccur –help for configuration options such as min-count or window-size.
GloVe models were introduced by Pennington et al., “Glove: global vectors for word representation”, ACL 2014.