# Neural Language Modeling

## Pre-trained models

Description | Dataset | Model | Test set(s)
---|---|---|---
Convolutional <br> ([Dauphin et al., 2017](https://arxiv.org/abs/1612.08083)) | [Google Billion Words](https://github.com/ciprian-chelba/1-billion-word-language-modeling-benchmark) | [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/models/lm/gbw_fconv_lm.tar.bz2) | [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/data/gbw_test_lm.tar.bz2)
Convolutional <br> ([Dauphin et al., 2017](https://arxiv.org/abs/1612.08083)) | [WikiText-103](https://einstein.ai/research/the-wikitext-long-term-dependency-language-modeling-dataset) | [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/models/wiki103_fconv_lm.tar.bz2) | [download (.tar.bz2)](https://dl.fbaipublicfiles.com/fairseq/data/wiki103_test_lm.tar.bz2)

## Example usage

These scripts provide an example of pre-processing data for the Language Modeling task.

### prepare-wikitext-103.sh

Provides an example of pre-processing for [WikiText-103 language modeling task](https://www.salesforce.com/products/einstein/ai-research/the-wikitext-dependency-language-modeling-dataset/):

Example usage:
```
$ cd examples/language_model/
$ bash prepare-wikitext-103.sh
$ cd ../..

# Binarize the dataset:
$ TEXT=examples/language_model/wikitext-103

$ fairseq-preprocess --only-source \
  --trainpref $TEXT/wiki.train.tokens --validpref $TEXT/wiki.valid.tokens --testpref $TEXT/wiki.test.tokens \ 
  --destdir data-bin/wikitext-103

# Train the model:
# If it runs out of memory, try to reduce max-tokens and max-target-positions
$ mkdir -p checkpoints/wikitext-103
$ fairseq-train --task language_modeling data-bin/wikitext-103 \
  --max-epoch 35 --arch fconv_lm_dauphin_wikitext103 --optimizer nag \
  --lr 1.0 --lr-scheduler reduce_lr_on_plateau --lr-shrink 0.5 \
  --clip-norm 0.1 --dropout 0.2 --weight-decay 5e-06 --criterion adaptive_loss \
  --adaptive-softmax-cutoff 10000,20000,200000 --max-tokens 1024 --tokens-per-sample 1024

# Evaluate:
$ fairseq-eval-lm data-bin/wikitext-103 --path 'checkpoints/wiki103/checkpoint_best.pt'

```