Ambiguity preserving analysis

[hiroshinoji]

The current CCG parser accepts one-best outputs from morphological analysis, but the outputs often contain errors. They cause a significant problem in constructing semantic representations along CCG derivations.

In order to solve this problem, the system is required to output n-best outputs, including not only ambiguities in CCG parsing but also those in morphological analysis. This requires some mechanism to pass ambiguity-preserving analyses from morphological analyzers to parsers.

The easiest solution is to modify the CCG parser to use lattice-style outputs from morphological analyzers. However, the problem of ambiguity preserving analysis is pervasive in various levels, and it is great if we can have some unified framework for this problem (maybe too ambitious?).