The l th GCN layer (l ∈ [1, L]) computed over the entire conversation structure can be written as an efficient matrix operation: where H (l−1) ∈ R |C|×d l−1 and H (l) ∈ R |C|×d l denote the input and output features of all tweets in the conversation C respectively.
the first GCN layer takes the content features of all tweets as input, i.e., H (0) = (c 1 , c 2 , .