Same probability from fine-tuning custom pre-trained LM
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## Details
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I have a dataset with QA sentence pairs. I pre-trained a bert model from scractch using run_language_modeling.py where I concatenated the QA pairs and trained the dataset line_by_line.

I tried to fine-tune the custom pre-trained model, but am getting the same probability output for different inputs. I also tried to reduce the learning rate, but the constant probability problem remains.

What could I be doing wrong?

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