(2017) adopt anonymization for dealing with the data sparsity problem.
they first replace the subgraphs that represent dates, numbers and named entities (such as "(q / quantity :quant 3)" and "(p / person :name (n / name :op1 "Ryan"))") with predefined placeholders (such as "num 0" and "person name 0") before decoding, and then recover the corresponding surface tokens (such as "3" and "Ryan") after decoding.