openai / finetune-transformer-lm

Code and model for the paper "Improving Language Understanding by Generative Pre-Training"
https://s3-us-west-2.amazonaws.com/openai-assets/research-covers/language-unsupervised/language_understanding_paper.pdf
MIT License
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Is the LM pre-trained with a _start_ symbol? #34

Open OanaMariaCamburu opened 5 years ago

OanaMariaCamburu commented 5 years ago

Hi,

I was wondering if, during the pre-training of the LM alone, the sentences were prepended with a start symbol, just like they are during fine-tuning. If that's the case, could you please mention what is the name of the token in the learned vocab? If that's not the case, then wouldn't it introduce a bit of a mismatch wrt the pre-trained LM? Of course, the model is being fine-tuned so it will adapt, but then why would the start symbol be necessary for fine-tuning? Thanks!