Redefining linguistic categories through network theory

Abstract

Categorization is a dynamic cognitive process that organizes human knowledge. As such, categorization processes are integral of the linguistic system and are primarily manifested in the conceptual categories represented in semantic memory. Linguistic theory has proposed various models to describe the nature and structure of semantic categories. This paper reviews the traditional definitions of four types of linguistic categories (natural or taxonomic, ad hoc, radial and scripts) from the complex network paradigm. The semantic networks have been constructed from a semantic fluency task (Animals, Objects laid on the table, Games and Countryside) involving 680 native Spanish speakers. Both the structure of the network and its dynamics are analysed, remarking the process by which speakers create the network through their linguistic performance. For this purpose, traditional mathematical measures from network theory were employed, and new measures were proposed to more precisely distinguish between the four types of categories. The results support the principles of linguistic description, expanding and refining the properties of the different types of semantic categories. Furthermore, they highlight the importance of fine-grained modularity measures as key to interpreting differences in conceptual categories.