An Experimental Discourse Structure 
Analyzer 

ABSTRACT 

An experimental analyzer for Japanese text which extracts "discourse struc-
ture" that expresses rhetorical and logical relation between sentences in the 
text.

We formalized the constraints on the discourse structure detected by rhetor-
ical expressions in the text, and the preference rules to the local structure 
depending on the occurrence of predefined surface expressions such as con-
nectives.

Features 

(I%(B Description for Discourse Structure 
  The 24 "Rhetorical Relations" are defined for discourse structure descrip-
  tion. 

(I%(B Segmentation Rule 
  "Segmentation Rules" capture the relations between Japanese surface 
  rhetorical expressions and the global constraints on the discourse struc-
  ture. 

(I%(B Thinking-flow Rule 
  "Thinking-flow Rules" are preference rules which express local constraints 
  on the sequence of rhetorical relations and sub-structures.