Formation mechanisms of local structures in language networks

Abstract

The small-world property has recently been observed in several language networks generated in terms of word co-occurrence. However, a syntactic interpretation of this universal property has not yet been clarified. This study aims to reveal the formation mechanism of local structures involving small-world properties of co-occurrence language networks. We analyse local structures of language networks with directed edges generated from five different languages, where the directed edges provide word-order information. The results show that the following three syntactic properties play a leading role in the formation of the local structure of a language network: i) agglutination of words, ii) changes in the positions of words, and iii) basic word orders of languages. We further show that a common formation mechanism exists in local structures, even though the syntactic rules vary between the considered languages. These syntactic properties potentially drive the small-world property of language networks.