By a similar analysis to the construction of the word cloud, the message texts were divided into a set of words by a morphological analysis and their frequencies were
5This means politely address someone such as Mr. X in Japanese.
6In general, a lecture in Japanese universities is 90 minutes long. In this case, the lecture commonly given at HCU and HSU is 85 minutes, because the daily schedules of both university have a difference of five minutes.