A ncient G reek W ord N et Meets the Dynamic Lexicon: the Example of the Fragments of the G reek Historians (2016)

Abstract: The Ancient Greek WordNet (AGWN) and the Dynamic Lexicon (DL) are multilingual resources to study the lexicon of Ancient Greek texts and their translations. Both AGWN and DL are works in progress that need accuracy improvement and manual validation. After a detailed description of the current state of each work, this paper illustrates a methodology to cross AGWN and DL data, in order to mutually score the items of each resource according to the evidence provided by the other resource. The training data is based on the corpus of the Digital Fragmenta Historicorum Graecorum (DFHG), which includes ancient Greek texts with Latin translations.

## introduction the ancient greek wordnet (agwn) and the dynamic lexicon (dl), which will be illustrated in detail in the next sections (see sections 2 and 4), are complementary resources to study the ancient greek lexicon. agwn is based on the paradigmatic axis provided by bilingual dictionaries, while dl is based on the syntagmatic axis provided by historical and literary texts aligned to their scholarly translations. both of them have been created automatically and they need to be corrected and extended. in this specific case the data is taken from the digital fragmenta historicorum graecorum (dfhg), which is a corpus of quotations and text reuses of ancient greek lost historians and their latin translations provided by the editor karl müller @xcite @xcite 1 . this corpus is part of lofts (leipzig open fragmentary texts series) at the ## ancient greek wordnet the creation of the ancient greek wordnet has been outlined in @xcite . it is based on digitized greek-english bilingual dictionaries (in particular the liddell-scott-jones and the middle liddell provided by the perseus project foot_0 ): first, greek-english pairs (greek words and english translations) are extracted from the dictionaries; then, the english word is projected onto the princeton wordnet (pwn) @xcite . if the english word is in pwn, then its synsets are assigned to the greek word; the same goes for its lexical relations with other lemmas. thus agwn is created "bootstrapping" data from different datasets. as a bootstrapped process, its result is quite inaccurate. for example, induced polysemy (from english) maps the greek verb ἔχω -échō-over 170 english words (including "cut", "make", "brake" . . . ). on the contrary, when the english word is not in pwn, the greek word of the pair is excluded from agwn, thus strongly reducing the coverage of agwn for the entire greek lexicon to c.a 30%. currently, agwn is linked not only to pwn, but also to other wordnets, in particular to the latin wordnet (lwn) @xcite and to the italian wordnet (iwn) @xcite . the way these wordnets are interconnected follows the guidelines illustrated in @xcite , by using english as the bridge language. as a consequence, greek and latin and/or greek and italian are linked through the common sense(s) in english. ## the conceptual structure of ancient greek wordnet sharing a unique conceptual network among different languages is a good solution when the civilizations expressed by those languages are very similar, due to the effects of the globalization. in this case, only few conceptual nodes must be inserted when a concept is lexicalized in the source language but not in the target language, and few nodes must be deactivated when a concept is only lexicalized in the target language, but not in the source language. on the contrary, when the civilizations expressed by the source and the target languages are highly dissimilar, the conceptual network needs to be heavily restructured. as illustrated in the introduction, the conceptual network of agwn is originally based on pwn, but the glosses of the synsets and the semantic relations can be modified through a web interface. foot_1 ## dynamic lexicon the dynamic lexicon is an increasing multilingual resource constituted by bilingual dictionaries (greek/english, latin/english, greek/latin), which have been created through the direct automated alignment of original texts with their translations or through a triangulation with a bridge language. the first version of the dl foot_2 is a national endowment for the humanities (neh) foot_3 co-funded project developed at tufts university (medford, ma) by the perseus project, whereas the second version is under development at the university of leipzig by the open philology. project foot_4 5 bilingual dictionary extraction this section investigates a simple and effective method for automatic extraction of a bilingual lexicon (ancient greek/latin) from the available aligned bilingual texts (greek/english and latin/english) in the perseus digital library using english as a bridge language. the data comes from the corpus of the dfhg and consists of 163 parallel documents aligned at a word level (104 ancient greek/english files and 59 latin/english). the greek-english dataset consists approximately of 210k sentence pairs with 4,32m greek words, whereas the latin-english dataset consists approximately of 123k sentence pairs with 2,33m latin words. the parallel texts are aligned on a sentence level using moore's bilingual sentence aligner @xcite , which aligns the sentences with a very high precision (one-to-one alignment). 7 then the giza++ toolkit foot_6 is used to align the sentence pairs at the level of individual words. ## future work the next step is the creation of a gold standard both for agwn and for dl, in order to quantify the gain in terms of precision and recall that we can obtain by crossing agwn and dl data. ## conclusion in conclusion, we think that the paradigmatic approach, by extraction of bilingual pairs from dictionaries, and the syntagmatic approach, by extraction of bilingual pairs from aligned texts, are complementary for the study of ancient greek semantics and that they can be integrated, in order to mutually improve the performances of both of them.