Russian dictionary with concreteness/abstractness indices

The demand for a Russian dictionary with indices of abstractness/concreteness of words has been expressed in a number of areas including linguistics, psychology, neurophysiology and cognitive studies focused on imaging concepts in human cognitive systems. Although dictionaries of abstractness/concreteness were compiled for a number of languages, Russian has been recently viewed as an under-resourced language for the lack of one. The Laboratory of Quantitative Linguistics of Kazan Federal University has implemented two methods of compiling dictionaries of abstract/concrete words, i.e. respondents survey and extrapolation of human estimates with the help of an original computer program. In this article, we provide a detailed description of the methodology used for assessing abstractness/concreteness of words by native Russian respondents, as well as control algorithms validating the survey quality. The implementation of the methodology has enabled us to create a Russian dictionary (1500 words) with indices of concreteness/abstractness of words, including those missing in the Russian Semantic Dictionary by N.Yu. Shvedova (1998). We have also created three versions of a machine dictionary of abstractness/concreteness based on the extrapolation of the respondents' ratings. The third, most accurate version contains 22,000 words and has been compiled with the use of a modern deep learning technology of neural networks. The paper provides statistical characteristics (histograms of the distribution of ratings, dispersion, etc.) of both the machine dictionary and the dictionary obtained by interviewing informants. The quality of the machine dictionary was validated on a test set of words by means of contrasting machine and human evaluations with the latter viewed as more credible. The purpose of the paper is to give a detailed description of the methodology employed to create a concrete/abstract dictionary, as well as to demonstrate the methodology of its application in theoretical and applied research on concrete examples. The paper shows the practical use of this vocabulary in six case studies: predicting the complexity of school textbooks as a function of the share of abstract words; comparing abstractness indices of Russian-English equivalents; assessing concreteness/abstractness of polysemantic words; contrasting ratings of different age groups of respondents; contrasting ratings of respondents with different levels of education; analyzing concepts of "concrete