Quantitative Analyses of Koji Uno’s Works before and after the Illness

Abstract

This manuscript aims to clarify the changes of Koji Uno’s writing styles after he suffered mental illness in 1927. In order to understand the differences in Uno’s works before and after his illness, a quantitative analysis using correspondence analysis and statistical hypothesis testing was employed. By analyzing the textual measurements, we found that his writing style after recovering from the illness is different from the previous. Both the frequency of Chinese characters and the vocabulary richness increased in the works written after the illness. These results, after further analysis, mainly consist of an increase in the use of nouns in later writings. Consequently, the overall writing style changed from spoken to written language. Furthermore, the overuse of the comma has an impact on the loss of the garrulity and fluency, which led to the changes in the style of the writings after the illness. Additionally, the work named ‘Nichiyobi’ which had been published before the disease treatment is more similar with the works written after recovering, indicating that the writing style had been changed even before the illness.