Thank you very much for your reply!
I'm performing an automatic sleep stage classification task using machine learning on SHHS 2.
I can't find if there are some PSG that come from the same patient, because to perform this task there can't be data coming from the same patient both in training and test dataset.
Reading the documentation it seems that each PSG(in SHHS2) come from a different patient, It's is right?
Thank you very much,