Bi-directional Attention Flow for Machine Comprehension
- This the original implementation of Bi-directional Attention Flow for Machine Comprehension (Seo et al., 2016).
- The CodaLab worksheet for the SQuAD Leaderboard submission is available here.
- Please contact Minjoon Seo (@seominjoon) for questions and suggestions.
- Python (verified on 3.5.2. Issues have been reported with Python 2!)
- unzip, wget (for running
- tensorflow (deep learning library, verified on r0.11)
- nltk (NLP tools, verified on 3.2.1)
- tqdm (progress bar, verified on 4.7.4)
- jinja2 (for visaulization; if you only train and test, not needed)
First, prepare data. Donwload SQuAD data and GloVe and nltk corpus
(~850 MB, this will download files to
chmod +x download.sh; ./download.sh
Second, Preprocess Stanford QA dataset (along with GloVe vectors) and save them in
$PWD/data/squad (~5 minutes):
python -m squad.prepro
The model was trained with NVidia Titan X (Pascal Architecture, 2016). The model requires at least 12GB of GPU RAM. If your GPU RAM is smaller than 12GB, you can either decrease batch size (performance might degrade), or you can use multi GPU (see below). The training converges at ~18k steps, and it took ~4s per step (i.e. ~20 hours).
Before training, it is recommended to first try the following code to verify everything is okay and memory is sufficient:
python -m basic.cli --mode train --noload --debug
Then to fully train, run:
python -m basic.cli --mode train --noload
You can speed up the training process with optimization flags:
python -m basic.cli --mode train --noload --len_opt --cluster
You can still omit them, but training will be much slower.
To test, run:
python -m basic.cli
Similarly to training, you can give the optimization flags to speed up test (5 minutes on dev data):
python -m basic.cli --len_opt --cluster
This command loads the most recently saved model during training and begins testing on the test data.
After the process ends, it prints F1 and EM scores, and also outputs a json file (
#### is the step # that the model was saved).
Note that the printed scores are not official (our scoring scheme is a bit harsher).
To obtain the official number, use the official evaluator (copied in
squad folder) and the output json file:
python squad/evaluate-v1.1.py $HOME/data/squad/dev-v1.1.json out/basic/00/answer/test-####.json
3.1 Loading from pre-trained weights
Instead of training the model yourself, you can choose to use pre-trained weights that were used for SQuAD Leaderboard submission. Refer to this worksheet in CodaLab to reproduce the results. If you are unfamiliar with CodaLab, follow these simple steps (given that you met all prereqs above):
save.zipfrom the worksheet and unzip it in the current directory.
glove.6B.100d.txtfrom your glove data folder (
$HOME/data/glove/) to the current directory.
To reproduce single model:
basic/run_single.sh $HOME/data/squad/dev-v1.1.json single.json
This writes the answers to
single.jsonin the current directory. You can then use the official evaluator to obtain EM and F1 scores. If you want to run on GPU (~5 mins), change the value of batch_size flag in the shell file to a higher number (60 for 12GB GPU RAM).
Similarly, to reproduce ensemble method:
basic/run_ensemble.sh $HOME/data/squad/dev-v1.1.json ensemble.json
If you want to run on GPU, you should run the script sequentially by removing '&' in the forloop, or you will need to specify different GPUs for each run of the for loop.
|EM (%)||F1 (%)|
|EM (%)||F1 (%)|
Multi-GPU Training & Testing
Our model supports multi-GPU training. We follow the parallelization paradigm described in TensorFlow Tutorial. In short, if you want to use batch size of 60 (default) but if you have 3 GPUs with 4GB of RAM, then you initialize each GPU with batch size of 20, and combine the gradients on CPU. This can be easily done by running:
python -m basic.cli --mode train --noload --num_gpus 3 --batch_size 20
Similarly, you can speed up your testing by:
python -m basic.cli --num_gpus 3 --batch_size 20