Language of Russian textbooks: diachronic linguistic profiling

The relevance of the research is conditioned by the need for a more complete understanding of the educational text as a genre with a multifunctional role in the educational process. When educational standards are revised and attention to the quality of textbooks is increased, the analysis of diachronic changes in the structure and content of Russian language textbooks becomes relevant to determine the main factors affecting the educational process. The aim of this study is to examine the linguistic specificity of text formants in Russian language textbooks and analyze the trends of their changes over time. The materials of the study include Russian language textbooks published in the Soviet Union (1935-1974) and in Russia (2012-2015). The research methods are based on the comparative analysis of linguistic parameters of formants ‘Exercises’ - ‘Tasks’ - ‘Theory’ and statistical tests to identify differences between these categories. The research showed statistically significant differences in most linguistic parameters, which confirm the thesis about the educational text heterogeneity. The most important differences among the formant categories were observed in the following parameters: Flesh-Kincaid Score, Global Noun Overlap, Type-Token Ratio, Singletons, Past Tense Verbs, Mean Sentence Length, Mean Word Length, Global Argument Overlap, and the Number of Nouns in the Genitive Case. Modern Russian language textbooks have lower lexical density and fewer nouns per 1000 tokens, higher local noun repetition, more frequent future tense verb forms, and higher global text coherence. These patterns reflect diachronic changes in the texts from Russian language textbooks. Future research should expand the range of the analyzed Russian language textbooks, particularly by including texts from textbooks for senior and elementary school, as well as a more detailed examination of the dynamics of linguistic parameter changes in Russian language textbooks during the Soviet period.