Text summarization based on rhetorical structure theory has shown extremely interesting result. The process of extracting the text summary from the result of the rhetorical parser is not a singleton. Different rhetorical structure trees are generated from one text. Unfortunately, the result of the generated summary is not equivalent for those trees, and the correctness of the result is affected...

This paper describes a study of the levels at which different rhetorical relations occur in rhetorical structure trees. In a previous empirical study (Williams and Reiter, 2003) of the RST-DT (Rhetorical Structure Theory Discourse Treebank) Corpus (Carlson et al., 2003), we noticed that certain rhetorical relations tended to occur more frequently at higher levels in a rhetorical structure tree,...