Training Issue: Zero Loss Values and "NA" Metrics in SEI Model with Pig Data

[zhuofanyan]

Hi
I am training the Sei model with pig data. However, during the training process, I noticed that all the loss values in the output file "selene_sdk.train_model.validation.txt" are consistently zero. Additionally, the metrics "average_precision" and "roc_auc" are reported as "NA" for all samples.

Considering your expertise in developing the SEI model, I am reaching out to seek your insights on the following questions:

1. Under what circumstances could all loss values be consistently zero during training? Could this indicate any specific issues or errors in the training process?
2. What could be the potential reasons behind the "NA" values for average_precision and roc_auc? Are there any common pitfalls or prerequisites that I might have overlooked?
   Thanks for your help!