Abstract
There are a lot of opportunities to read or write documents in our social activities. A document, that is easy to comprehend, has a document stream throughout, and relationships among consecutive segments are clarity. If a document stream can be extracted and evaluated quantitatively, some support systems that enable us to comprehend or create documents will be suggested.
In this paper, we propose a sub-topic model that models a document stream, and criterion to evaluate a document stream quantatively. Some preliminary experiments were executed to show validity of this model, and proposing criterion for document stream were evaluated by segments ordering experiments.
