Abstract
To more accurately assess the logical structure of Japanese essays, I have devised a technique that uses end-of-sentence modality and demonstrative pronouns referencing earlier paragraphs as new indicators of structure in addition to conjunctive expressions which have hitherto often used for Japanese as well as for European languages. It is hoped that this will yield better results because conjunctive expressions are intentionally avoided in Japanese. I applied this technique to the editorial and commentary (Yoroku) columns of the Mainichi Shimbun newspaper and used it to represent the structure and development of the arguments made by these articles in the form of constellation diagrams which are used in the field of statistics. As a result, I found that this graph is useful in that it enables the overall distribution to be ascertained, and allows the temporal changes in the logical structure of the data in question to be ascertained.
