International Conference on Computational Linguistics in Bulgaria (2020)


pdf (full)
bib (full)
Proceedings of the 4th International Conference on Computational Linguistics in Bulgaria (CLIB 2020)

pdf bib
Proceedings of the 4th International Conference on Computational Linguistics in Bulgaria (CLIB 2020)

pdf bib
A Corpus-based Study of Derivational Morphology and its Theoretical Implications
Junya Morita

The present study investigates the formal and semantic properties of derivational morphology, dealing in particular with -able derivatives in English (e.g. the recorder is pocketable ). Focusing principally on hapax legomena in a large corpus, a reliable indicator of online coinage, -able derivatives are extracted from it. Detailed observation of them is carried out and then their theoretical analysis is conducted in the framework of generative morphology. The data analysis elucidates (i) a core aspect of -able : it productively attaches to transitive verbs to produce modalized passive adjectives whose external arguments are restricted to Theme arguments and (ii) a peripheral facet: the basic meaning of -able as well as its prototypical base category and external argument are extended, on a small scale, to other kinds of meaning and category. Based on these empirical observations, major and minor formation rules are proposed to deal respectively with regular and sub-regular -able derivation.

pdf bib
Syntactic and morphological features after verbs of perception: Bulgarian in Balkan context
Ekaterina Tarpomanova

The paper analyses the types of constructions that express a subordinate event after a verb of perception in the languages of the Balkan Sprachbund. The subordinate clauses that may follow a verb of perception are a result of common historical processes in Bulgarian, Albanian, Romanian and Greek: the substitution of infinitive by subjunctive and the neutralization of modal and declarative conjunctions after verbs of perception. Additionally, in Albanian and Romanian among the non-finite verbal forms gerund may be found after perception verbs. For the analysed syntactic structures in Bulgarian a corpus approach is further applied in order to support the linguistic analysis with quantitative data.

On the Valency Frames of type Subject-Predicate in Bulgarian
Petya Osenova

The paper presents some observations on the semantic constraints of the intransitive subjects with respect to the predicates they combine with. For these observations a valency dictionary of Bulgarian was used. Here two clarifications are to be made. First, the intransitive predicates are viewed in a broader perspective. They combine true intransitives as well as intransitive usages of transitive verbs. The complexity comes from the modeling of these verbs in the morphological dictionary. Second, the semantic constraints that are considered here, are limited to a set of semantic roles and build on the lexicographic classes of verbs in WordNet.

Analysis of Similes in Serbian Literary Texts (1860-1920) using computational methods
Cvetana Krstev | Jelena Jaćimović | Duško Vitas

Similes are rhetorical figures which play an important role in literary texts. This paper presents a finite-state methodology developed for the description of adjectival similes, which enables their retrieval and annotation in Serbian novels written in the mid-19th and early 20th centuries. The results of a textometric analysis reveal the most frequent adjectival similes and the specificity of their usage, with respect to the author, title, or publication date, in a subset of the SrpELTeC corpus.

Classification of L2 Thesis Statement Writing Performance Using Syntactic Complexity Indices
Kutay Uzun

This study primarily aimed to find out if machine learning classification algorithms could accurately classify L2 thesis statement writing performance as high or low using syntactic complexity indices. Secondarily, the study aimed to reveal how the syntactic complexity indices from which classification algorithms gained the largest amount of information interacted with L2 thesis statement writing performance. The data set of the study consisted of 137 high-performing and 69 low-performing thesis statements written by undergraduate learners of English in a foreign language context. Experiments revealed that the Locally Weighted Learning algorithm could classify L2 thesis statement writing performance with 75.61% accuracy, 20.01% above the baseline. Balancing the data set via Synthetic Minority Oversampling produced the same accuracy percentage with the Stochastic Gradient Descent algorithm, resulting in a slight increase in Kappa Statistic. In both imbalanced and balanced data sets, it was seen that the number of coordinate phrases, coordinate phrase per t-unit, coordinate phrase per clause and verb phrase per t-unit were the variables from which the classification algorithms gained the largest amount of information. Mann-Whitney U tests showed that the high-performing thesis statements had a larger amount of coordinate phrases and higher ratios of coordinate phrase per t-unit and coordinate phrase per clause. The verb phrase per t-unit ratio was seen to be lower in high-performing thesis statements than their low-performing counterparts.

Categorisation of Bulgarian Legislative Documents
Nikola Obreshkov | Martin Yalamov | Svetla Koeva

The paper presents the categorisation of Bulgarian MARCELL corpus in toplevel EuroVoc domains. The Bulgarian MARCELL corpus is part of a recently developed multilingual corpus representing the national legislation in seven European countries. We performed several experiments with JEX Indexer, with neural networks and with a basic method measuring the domain-specific terms in documents annotated in advance with IATE terms and EuroVoc descriptors (combined with grouping of a primary document and its satellites, term extraction and parsing of the titles of the documents). The evaluation shows slight overweight of the basic method, which makes it appropriate as the categorisation should be a module of a NLP Pipeline for Bulgarian that is continuously feeding and annotating the Bulgarian MARCELL corpus with newly issued legislative documents.

Controlling Chat Bot Multi-Document Navigation with the Extended Discourse Trees
Dmitry Ilvovsky | Alexander Kirillovich | Boris Galitsky

In this paper we learn how to manage a dialogue relying on discourse of its utterances. We define extended discourse trees, introduce means to manipulate with them, and outline scenarios of multi-document navigation to extend the abilities of the interactive information retrieval-based chat bot. We also provide evaluation results of the comparison between conventional search and chat bot enriched with the multi-document navigation.

Cross-lingual Transfer Learning for Semantic Role Labeling in Russian
Ilseyar Alimova | Elena Tutubalina | Alexander Kirillovich

This work is devoted to semantic role labeling (SRL) task in Russian. We investigate the role of transfer learning strategies between English FrameNet and Russian FrameBank corpora. We perform experiments with embeddings obtained from various types of multilingual language models, including BERT, XLM-R, MUSE, and LASER. For evaluation, we use a Russian FrameBank dataset. As source data for transfer learning, we experimented with the full version of FrameNet and the reduced dataset with a smaller number of semantic roles identical to FrameBank. Evaluation results demonstrate that BERT embeddings show the best transfer capabilities. The model with pretraining on the reduced English SRL data and fine-tuning on the Russian SRL data show macro-averaged F1-measure of 79.8%, which is above our baseline of 78.4%.

Description Logic Based Formal Representation of Adjectives
Maria Grits

The paper introduces a system of rules for description logic based formal representation of adjectives used in both attributive and predicative functions and involved in a variety of syntactic relations. The system was developed to convey the semantics of adjectives by virtue of concept and role constructors implemented in description logic formalisms known as SHOIN(D) and SROIQ(D). The system is intended to be integrated into a large-scale system of formalization rules devised for the development of description logic based definitions of domain terms. The proposed system of rules was tested and evaluated on two sets of syntactic units that contain attributive and predicative adjectives represented in English and Russian languages.

Linguistic vs. encyclopedic knowledge. Classification of MWEs on the base of domain information
Zara Kancheva | Ivaylo Radev

This paper reports on the first steps in the creation of linked data through the mapping of BTB-WordNet and the Bulgarian Wikipedia. The task of expanding the BTB-WordNet with encyclopedic knowledge is done by mapping its synsets to Wikipedia pages with many MWEs found in the articles and subjected to further analysis. We look for a way to filter the Wikipedia MWEs in the effort of selecting the ones most beneficial to the enrichment of BTB-WN.

It Takes Two to Tango – Towards a Multilingual MWE Resource
Svetlozara Leseva | Verginica Barbu Mititelu | Ivelina Stoyanova

Mature wordnets offer the opportunity of digging out interesting linguistic information otherwise not explicitly marked in the network. The focus in this paper is on the ways the results already obtained at two levels, derivation and multiword expressions, may be further employed. The parallel recent development of the two resources under discussion, the Bulgarian and the Romanian wordnets, has enabled interlingual analyses that reveal similarities and differences between the linguistic knowledge encoded in the two wordnets. In this paper we show how the resources developed and the knowledge gained are put together towards devising a linked MWE resource that is informed by layered dictionary representation and corpus annotation and analysis. This work is a proof of concept for the adopted method of compiling a multilingual MWE resource on the basis of information extracted from the Bulgarian, the Romanian and the Princeton wordnet, as well as additional language resources and automatic procedures.

Generating Natural Language Numerals with TeX
Ivan Derzhanski | Milena Veneva

Sometimes one needs to produce a text in which many numbers have to be written out in words. Writing such a text and ensuring it is error-free can be a burden, especially if the author is not fluent in the language. Such may occur when working on a reference grammar, a research paper or presentation, or a problem on number names for a contest in linguistics. A remedy is to prepare the text with TEX and let some parts be generated automatically. The human effort this takes is to compose a grammar that describes the features of the numeral system. This paper discusses how this is done.

A Natural Language for Bulgarian Primary and Secondary Education
Iglika Nikolova-Stoupak

This paper examines the qualities and applicability of a provisional programming language, especially designed for use by beginner-level students in Bulgarian primary and secondary schools. The necessity for such a language is investigated. Then, relevant features are defined, as inspired by various programming languages (notably, languages used in education and characterised with non- English syntax) and by general trends related to the achievement of natural language in software development. A survey is conducted to test young students’ interaction with the language, and the latter’s advantages and limitations are listed and discussed.

Digital Edition of the Life of St. Petka
Ivan Šimko

This paper presents the construction of a digital edition of multiple versions of the hagiography of St. Petka of Tarnovo. Two related versions are uploaded at first: a Church Slavonic print edition and its later damaskini redaction. Both texts are adapted for user-friendly reading with side-by-side facsimiles. Translations and additional data concerning separate tokens and sentences can be shown up by the cursor on fly. Further metadata will be available for search. Annotation has been adapted for the transitionary status of the language of the texts: it allows us to compare similar morphological forms with various functions. The edition has already been published online and can be used for both teaching and studying. The texts have been digitalized as a part of a larger project concerning the development of the Balkan areal features.

A Bilingual Lexicosemantic Network of Bread Based on a Parallel Corpus
Ivan Derzhanski | Olena Siruk

We present an experiment in using a corpus of Bulgarian and Ukrainian parallel texts for the automatised construction of a bilingual lexicosemantic network representing the semantic field of BREAD. We discuss the extraction of the relevant material from the corpus, the production of networks with varying parameters, some issues of the interpretation of these networks, and possible ways of making them more accurate and informative.

A Customizable WordNet Editor
Andrei-Marius Avram | Verginica Barbu Mititelu

This paper presents an open-source wordnet editor that has been developed to ensure further expansion of the Romanian wordnet. It comes with a web interface that offers capabilities in selecting new synsets to be implemented, editing the list of literals and their sense numbers and adding these new synsets to the existing network, by importing from Princeton WordNet (and adjusting, when necessary) all the relations in which the newly created synsets and their literals are involved. The application also comes with an authorization mechanism that ensures control of the new synsets added in novice or lexicographer accounts. Although created to serve the current (more or less specific) needs in the development of the Romanian wordnet, it can be customized to fulfill new requirements from developers, either of the same wordnet or of a different one for which a similar approach is adopted.

Comparison of Genres in Word Sense Disambiguation using Automatically Generated Text Collections
Angelina Bolshina | Natalia Loukachevitch

The best approaches in Word Sense Disambiguation (WSD) are supervised and rely on large amounts of hand-labelled data, which is not always available and costly to create. In our work we describe an approach that is used to create an automatically labelled collection based on the monosemous relatives (related unambiguous entries) for Russian. The main contribution of our work is that we extracted monosemous relatives that can be located at relatively long distances from a target ambiguous word and ranked them according to the similarity measure to the target sense. We evaluated word sense disambiguation models based on a nearest neighbour classification on BERT and ELMo embeddings and two text collections. Our work relies on the Russian wordnet RuWordNet.

Consistency Evaluation towards Enhancing the Conceptual Representation of Verbs in WordNet
Svetlozara Leseva | Ivelina Stoyanova

This paper outlines the process of enhancing the conceptual description of verb synsets in WordNet using FrameNet frames. On the one hand we expand the coverage of the mapping between WordNet and FrameNet, while on the other – we improve the quality of the mapping using a set of consistency checks and verification procedures. The procedures include an automatic identification of potential inconsistencies and imbalanced relations, as well as suggestions for a more precise frame assignment followed by manual validation. We perform an evaluation of the procedures in terms of the quality of the suggestions measured as the potential improvement in precision and coverage, the relevance of the result and the efficiency of the procedure.

On WordNet Semantic Classes: Is the Sum Always Bigger?
Tsvetana Dimitrova

The paper offers an approach to the validation of the data resulted from a previous effort on expansion of WordNet noun semantic classes by mapping them with the semantic types within the Corpus Pattern Analysis (CPA) ontology employed by the framework of the Pattern Dictionary of English Verbs (PDEV). A case study is presented along with a set of conditions to be checked when validating the combined data.