PTB treebank from CoNLL-X

Question

I have a CoNLL-X format treebank and the corresponding binary parse tree for each sentence and I want to convert it into a PTB format. Is there any converters or can anyone shed light on the PTB format?

Answer 1

There's been a number of efforts to convert from dependencies (representable in CoNLL-X format) to constituents (representable in Penn Treebank, or PTB, format). Two recent papers and their code:

1. Transforming Dependencies into Phrase Structures (Kong, Rush, and Smith, NAACL 2015). Code.

2. Parsing as Reduction (Fernandez-Gonzalez and Martins, ACL 2015). Code.