Inferring inflection classes with description length

Sacha Beniamine,Olivier Bonami,Benoît Sagot

doi:10.15398/jlm.v5i3.184

Abstract

We discuss the notion of an inflection class system, a traditional ingredient of the description of inflection systems of nontrivial complexity. We distinguish systems of microclasses, which partition a set of lexemes in classes with identical behavior, and systems of macroclasses, which group lexemes that are similar enough in a few larger classes. On the basis of the intuition that macroclasses should contribute to a concise description of the system, we propose one algorithmic method for inferring macroclasses from raw inflectional paradigms, based on minimisation of the description length of the system under a given strategy for identifying morphological alternations in paradigms. We then exhibit classifications produced by our implementation on French and European Portuguese conjugation data, and argue that they constitute an appropriate systematisation of traditional classifications. To arrive at such a concincing systematisation, it is crucial though that we use a local approach to class similarity (based on pairwise comparisons of paradigm cells) rather than a global approach (based on simultaneous comparison of all cells). We conclude that it is indeed possible to infer inflectional macroclasses objectively.

Highlights

The concept of inflection class is central to many analyses of inflection systems, both in theoretical linguistics and in psycholinguistic studies
We show that inflection classes can be deduced in a systematic and motivated way from raw paradigms, without introducing any preconception about organizing principles other than similarity
Inferring inflection classes with description length and show that a local approach captures the kinds of generalizations that descriptive morphologists rely on for classification

Summary

Introduction

The concept of inflection class is central to many analyses of inflection systems, both in theoretical linguistics (see among many others Matthews 1972; Carstairs 1987; Wurzel 1989; Aronoff 1994; Dressler and Thornton 1996; Corbett 2009) and in psycholinguistic studies (see among others Milin et al 2009; Veríssimo and Clahsen 2014). To avoid making any undermotivated decision as to the boundary between affixal exponence and stem allomophy, we define inflectional realisation in terms of the alternation patterns relating the different forms in the paradigm of a lexeme to each other.

Objectives

Results

Conclusion