June 11, 2020

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multi_task_NLP is a utility toolkit enabling NLP developers to easily train and infer a single model for multiple tasks.

repo name hellohaptik/multi-task-NLP
repo link https://github.com/hellohaptik/multi-task-NLP
homepage https://multi-task-nlp.readthedocs.io/en/latest/
language Python
size (curr.) 7830 kB
stars (curr.) 142
created 2020-03-31
license Apache License 2.0

multi_task_NLP is a utility toolkit enabling NLP developers to easily train and infer a single model for multiple tasks. We support various data formats for majority of NLU tasks and multiple transformer-based encoders (eg. BERT, Distil-BERT, ALBERT, RoBERTa, XLNET etc.)

For complete documentation for this library, please refer to documentation

What is multi_task_NLP about?

Any conversational AI system involves building multiple components to perform various tasks and a pipeline to stitch all components together. Provided the recent effectiveness of transformer-based models in NLP, it’s very common to build a transformer-based model to solve your use case. But having multiple such models running together for a conversational AI system can lead to expensive resource consumption, increased latencies for predictions and make the system difficult to manage. This poses a real challenge for anyone who wants to build a conversational AI system in a simplistic way.

multi_task_NLP gives you the capability to define multiple tasks together and train a single model which simultaneously learns on all defined tasks. This means one can perform multiple tasks with latency and resource consumption equivalent to a single task.


To use multi-task-NLP, you can clone the repository into the desired location on your system with the following terminal command.

$ cd /desired/location/
$ git clone https://github.com/hellohaptik/multi-task-NLP.git
$ cd multi-task-NLP
$ pip install -r requirements.txt 

NOTE:- The library is built and tested using Python 3.7.3. It is recommended to install the requirements in a virtual environment.

Quickstart Guide

A quick guide to show how a model can be trained for single/multiple NLU tasks in just 3 simple steps and with no requirement to code!!

Follow these 3 simple steps to train your multi-task model!

Step 1 - Define your task file

Task file is a YAML format file where you can add all your tasks for which you want to train a multi-task model.

    model_type: BERT
    config_name: bert-base-uncased
    dropout_prob: 0.05
    - label1
    - label2
    - label3
    - accuracy
    loss_type: CrossEntropyLoss
    task_type: SingleSenClassification
    - taskA_train.tsv
    - taskA_dev.tsv
    - taskA_test.tsv

    model_type: BERT
    config_name: bert-base-uncased
    dropout_prob: 0.3
    label_map_or_file: data/taskB_train_label_map.joblib
    - seq_f1
    - seq_precision
    - seq_recall
    loss_type: NERLoss
    task_type: NER
    - taskB_train.tsv
    - taskB_dev.tsv
    - taskB_test.tsv

For knowing about the task file parameters to make your task file, task file parameters.

Step 2 - Run data preparation

After defining the task file, run the following command to prepare the data.

$ python data_preparation.py \ 
    --task_file 'sample_task_file.yml' \
    --data_dir 'data' \
    --max_seq_len 50

For knowing about the data_preparation.py script and its arguments, refer running data preparation.

Step 3 - Run train

Finally you can start your training using the following command.

$ python train.py \
    --data_dir 'data/bert-base-uncased_prepared_data' \
    --task_file 'sample_task_file.yml' \
    --out_dir 'sample_out' \
    --epochs 5 \
    --train_batch_size 4 \
    --eval_batch_size 8 \
    --grad_accumulation_steps 2 \
    --log_per_updates 25 \
    --save_per_updates 1000 \
    --eval_while_train True \
    --test_while_train True \
    --max_seq_len 50 \
    --silent True 

For knowing about the train.py script and its arguments, refer running train

How to Infer?

Once you have a multi-task model trained on your tasks, we provide a convenient and easy way to use it for getting predictions on samples through the inference pipeline.

For running inference on samples using a trained model for say TaskA, TaskB and TaskC, you can import InferPipeline class and load the corresponding multi-task model by making an object of this class.

>>> from infer_pipeline import inferPipeline
>>> pipe = inferPipeline(modelPath = 'sample_out_dir/multi_task_model.pt', maxSeqLen = 50)

infer function can be called to get the predictions for input samples for the mentioned tasks.

>>> samples = [ ['sample_sentence_1'], ['sample_sentence_2'] ]
>>> tasks = ['TaskA', 'TaskB']
>>> pipe.infer(samples, tasks)

For knowing about the infer_pipeline, refer infer.


Here you can find various conversational AI tasks as examples and can train multi-task models in simple steps mentioned in the notebooks.

Example-1 Intent detection, NER, Fragment detection

(Setup : Multi-task , Task type : Multiple)

Intent Detection(Task type : Single sentence classification)

 Query: I need a reservation for a bar in bangladesh on feb the 11th 2032
 Intent: BookRestaurant

NER (Task type :sequence labelling)

Query: ['book', 'a', 'spot', 'for', 'ten', 'at', 'a', 'top-rated', 'caucasian', 'restaurant', 'not', 'far', 'from', 'selmer']

NER tags: ['O', 'O', 'O', 'O', 'B-party_size_number', 'O', 'O', 'B-sort', 'B-cuisine', 'B-restaurant_type', 'B-spatial_relation', 'I-spatial_relation', 'O', 'B-city']

Fragment Detection (Task type : single sentence classification)

Query: a reservation for

Label: fragment

Notebook :- intent_ner_fragment

Transform file :- transform_file_snips

Tasks file :- tasks_file_snips

Example-2 Entailment detection

(Setup : single-task , Task type : sentence pair classification)

Query1: An old man with a package poses in front of an advertisement.

Query2: A man poses in front of an ad.

Label: entailment

Query1: An old man with a package poses in front of an advertisement.

Query2: A man poses in front of an ad for beer.

Label: non-entailment

Notebook :- entailment_snli

Transform file :- transform_file_snli

Tasks file :- tasks_file_snli

Example-3 Answerability detection

(Setup : single-task , Task type : sentence pair classification)

Query: how much money did evander holyfield make

Context: Evander Holyfield Net Worth. How much is Evander Holyfield Worth? Evander Holyfield Net Worth: Evander Holyfield is a retired American professional boxer who has a net worth of $500 thousand. A professional boxer, Evander Holyfield has fought at the Heavyweight, Cruiserweight, and Light-Heavyweight Divisions, and won a Bronze medal a the 1984 Olympic Games.

Label: answerable

Notebook :- answerability_detection_msmarco

Transform file :- transform_file_answerability

Tasks file :- tasks_file_answerability

Example-4 Query type detection

(Setup : single-task , Task type : single sentence classification)

Query: what's the distance between destin florida and birmingham alabama?


Query: who is suing scott wolter


Notebook :- query_type_detection

Transform file :- transform_file_querytype

Tasks file :- tasks_file_querytype

Example-5 POS tagging, NER tagging

(Setup : Multi-task , Task type : sequence labelling)

Query: ['Despite', 'winning', 'the', 'Asian', 'Games', 'title', 'two', 'years', 'ago', ',', 'Uzbekistan', 'are', 'in', 'the', 'finals', 'as', 'outsiders', '.']

NER tags: ['O', 'O', 'O', 'I-MISC', 'I-MISC', 'O', 'O', 'O', 'O', 'O', 'I-LOC', 'O', 'O', 'O', 'O', 'O', 'O', 'O']

POS tags: ['I-PP', 'I-VP', 'I-NP', 'I-NP', 'I-NP', 'I-NP', 'B-NP', 'I-NP', 'I-ADVP', 'O', 'I-NP', 'I-VP', 'I-PP', 'I-NP', 'I-NP', 'I-SBAR', 'I-NP', 'O']

Notebook :- ner_pos_tagging_conll

Transform file :- transform_file_conll

Tasks file :- tasks_file_conll

Example-6 Query correctness

(Setup : single-task , Task type : single sentence classification)

Query: What places have the oligarchy government ?

Label: well-formed

Query: What day of Diwali in 1980 ?

Label: not well-formed

Notebook :- query_correctness

Transform file :- transform_file_query_correctness

Tasks file :- tasks_file_query_correctness

Example-7 Query similarity

(Setup : single-task , Task type : single sentence classification)

Query1: What is the most used word in Malayalam?

Query2: What is meaning of the Malayalam word ""thumbatthu""?

Label: not similar

Query1: Which is the best compliment you have ever received?

Query2: What's the best compliment you've got?

Label: similar

Notebook :- query_similarity

Transform file :- transform_file_qqp

Tasks file :- tasks_file_qqp

Example-8 Sentiment Analysis

(Setup : single-task , Task type : single sentence classification)

Review: What I enjoyed most in this film was the scenery of Corfu, being Greek I adore my country and I liked the flattering director's point of view. Based on a true story during the years when Greece was struggling to stand on her own two feet through war, Nazis and hardship. An Italian soldier and a Greek girl fall in love but the times are hard and they have a lot of sacrifices to make. Nicholas Cage looking great in a uniform gives a passionate account of this unfulfilled (in the beginning) love. I adored Christian Bale playing Mandras the heroine's husband-to-be, he looks very very good as a Greek, his personality matched the one of the Greek patriot! A true fighter in there, or what! One of the movies I would like to buy and keep it in my collection...for ever!

Label: positive

Notebook :- IMDb_sentiment_analysis

Transform file :- transform_file_imdb

Tasks file :- tasks_file_imdb

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