Fig 2. A schematic diagram of the neural network architecture of (ABSA)² for classifying antibody specificity snippets.

(ABSA)² is an attention-over-attention model (AOA) based on ABSA [18] but with a transformer (left) as its input word embedding layer. (ABSA)² takes a snippet and an aspect token “antibody” as the input to classify the snippet into one of the specificity classes.