The prediction accuracy for the masked token is ZERO when using the pretrained model. Does it make sense?
Hi, this question might be not relavent to the code but to BERT, I still hope I can find someone to help me out. 

I run the pretrained model BertForPreTraining and test it on my own text data. Because BERT has knowledge about language so I expect it to be able to predict the masked tokens with a reasonable accuracy, however it is zero. I run the model with model.eval() mode. Does it make sense that it predicts the masked tokens with zero? 

Thanks for the help.