Difference between observed_feat_dynamic_real and feat_dynamic_real?

[GeoffNN]

Hi -- great work, thanks for releasing the paper and codebase!

I was digging through the code and noticed that the forward in the lightning model takes feat_dynamic_real and observed_feat_dynamic_real, but I couldn't find any reference to the observed variant in the examples. Same thing for past_dynamic_real and past_observed_dynamic_real.
Could you expand on the difference between the two?
Thanks

[gorold]

observed is a binary tensor, indicating whether the corresponding value is observed or not (1 for observed, 0 for unobserved i.e. missing value).