We use a Multi Layer Perceptron (MLP) for each task and then a softmax layer to obtain prediction probabilites.
given the vector z we pass it to n MLPs and obtain n output vectors y (i) : We are only interested in the output y (1) and the rest of outputs (y (2) , ..., y (n) ) are regarding the scaffold tasks and only used in training to inform the model of knowledge in the structure of the scientific documents.