Time of the day in Latvian: corpus-based study

Students of medical sciences at Rīga Stradiņš University attend a mandatory course of Latvian which aims to enable a conversation between the student and a patient in later stages of the study process. One of the cultural aspects often overlooked is understanding the time of the day, e.g., the notion of "night" can be understood differently by native speakers of Latvian and English. This may lead to misunderstandings when discussing the progression of symptoms and/or instructing the patient. Thus, the objective of this research is to discuss the understanding of terms "night", "morning", "day", "afternoon", "evening" in Latvian for teaching them more efficiently in the future. The Balanced Corpus of Modern Latvian is used to extract phrases containing exact time (hours and minutes) together with a time of the day, such as "trīs naktī" 'three in the night', used instead of "three P.M." in Latvian. The co-occurrences of each hour with each time of the day were counted to establish a pattern. The hours from 23:01 to 3:00 seem to be most strongly related to the night, from 3:01 to 11:00 – to the morning, from 11:01 to 16:00 – to the day or afternoon, and from 16:01 to 23:00 – to the evening. However, the hours from 10:01 to 13:00, from 15:01 to 17:00, and from 23:01 to 24:00 have a low occurrence frequency which suggests the need for a larger reference corpus. The borders between respective times of the day are somewhat fuzzy, e.g., 4:00 can be considered either night or morning. However, the discovered time slots can be used as guidelines for foreign medical professionals trying to understand their patients better and instruct them precisely. These results are also useful for Latvian language teachers helping learners understand the alternatives to A.M. and P.M. in Latvian.