Need help with understanding of confidence scores|HF Transformers Question Answering

Hello All,

I am working on the Question-Answering problems and would like to know how the model confidence scores are calculated ? What is the formula as well as theory behind it ?

I get scores as 4.5, 3.5678, 9.456 etc. for the predicted answers and sometimes these scores are negative values.

I am not sure if the confidence score can be -ve if it’s the product of two softmax probabilities.