projecte-aina/aina-translator-ca-pt

Projecte Aina’s Catalan-Portuguese machine translation model

Model description

This model was trained from scratch using the Fairseq toolkit on a combination of datasets comprising both Catalan-Portuguese data sourced from Opus, and additional datasets where synthetic Catalan was generated from the Spanish side of Spanish-Portuguese corpora using Projecte Aina’s Spanish-Catalan model. This gave a total of approximately 100 million sentence pairs. The model is evaluated on the Flores, NTEU and NTREX evaluation sets.  

Intended uses and limitations

You can use this model for machine translation from Catalan to Portuguese.

How to use

Usage

Required libraries:

pip install ctranslate2 pyonmttok

Translate a sentence using python

import ctranslate2
import pyonmttok
from huggingface_hub import snapshot_download
model_dir = snapshot_download(repo_id="projecte-aina/aina-translator-ca-pt", revision="main")

tokenizer=pyonmttok.Tokenizer(mode="none", sp_model_path = model_dir + "/spm.model")
tokenized=tokenizer.tokenize("Benvingut al projecte Aina!")

translator = ctranslate2.Translator(model_dir)
translated = translator.translate_batch([tokenized[0]])
print(tokenizer.detokenize(translated[0][0]['tokens']))

Limitations and bias

At the time of submission, no measures have been taken to estimate the bias and toxicity embedded in the model. However, we are well aware that our models may be biased. We intend to conduct research in these areas in the future, and if completed, this model card will be updated.

Training

Training data

The model was trained on a combination of the following datasets:

Datasets
DGT
EU Bookshop
Europarl
Global Voices
GNOME
KDE 4
Multi CCAligned
Multi Paracrawl
Multi UN
NLLB
NTEU
Open Subtitles
Tatoeba
UNPC
WikiMatrix

All corpora except Europarl were collected from Opus and ELRC. The Europarl corpus is a synthetic parallel corpus created from the original Spanish-Catalan corpus by SoftCatalà. After all Catalan-Portuguese data had been collected, Spanish-Portuguese data was collected and the Spanish data translated to Catalan using Projecte Aina’s Spanish-Catalan model.

Training procedure

Data preparation

All datasets are deduplicated, filtered for language identification, and filtered to remove any sentence pairs with a cosine similarity of less than 0.75. This is done using sentence embeddings calculated using LaBSE. The filtered datasets are then concatenated to form the final corpus. Before training the punctuation is normalized using a modified version of the join-single-file.py script from SoftCatalà

Tokenization

All data is tokenized using sentencepiece, with a 50 thousand token sentencepiece model learned from the combination of all filtered training data. This model is included.

Hyperparameters

The model is based on the Transformer-XLarge proposed by Subramanian et al. The following hyperparameters were set on the Fairseq toolkit:

Hyperparameter	Value
Architecture	transformer_vaswani_wmt_en_de_big
Embedding size	1024
Feedforward size	4096
Number of heads	16
Encoder layers	24
Decoder layers	6
Normalize before attention	True
--share-decoder-input-output-embed	True
--share-all-embeddings	True
Effective batch size	48.000
Optimizer	adam
Adam betas	(0.9, 0.980)
Clip norm	0.0
Learning rate	5e-4
Lr. schedurer	inverse sqrt
Warmup updates	8000
Dropout	0.1
Label smoothing	0.1

The model was trained for a total of 17.000 updates. Weights were saved every 1000 updates and reported results are the average of the last 2 checkpoints.

Evaluation

Variable and metrics

We use the BLEU score for evaluation on the Flores-101, NTEU (unpublished), and NTREX test sets.

Evaluation results

Below are the evaluation results on the machine translation from Catalan to Portuguese compared to Softcatalà and Google Translate:

Test set	SoftCatalà	Google Translate	aina-translator-ca-pt
Flores 101 dev	30,8	39,7	38,5
Flores 101 devtest	31,5	39	39
NTEU	41,7	47,1	57,4
NTREX	27,9	30,2	28,9
Average	33	39	41

Additional information

Author

The Language Technologies Unit from Barcelona Supercomputing Center.

Contact

For further information, please send an email to langtech@bsc.es.

Copyright

Copyright(c) 2023 by Language Technologies Unit, Barcelona Supercomputing Center.

License

Apache License, Version 2.0

Funding

This work has been promoted and financed by the Generalitat de Catalunya through the Aina project.

Disclaimer

Click to expand

The model published in this repository is intended for a generalist purpose and is available to third parties under a permissive Apache License, Version 2.0.

Be aware that the model may have biases and/or any other undesirable distortions.

When third parties deploy or provide systems and/or services to other parties using this model (or any system based on it) or become users of the model, they should note that it is their responsibility to mitigate the risks arising from its use and, in any event, to comply with applicable regulations, including regulations regarding the use of Artificial Intelligence.

In no event shall the owner and creator of the model (Barcelona Supercomputing Center) be liable for any results arising from the use made by third parties.