Modelling the Diachronic Emergence of Phoneme Frequency Distributions

2026-03-10

AI Summary

This study investigates whether cross-linguistic statistical regularities in phoneme frequency distributions—such as the exponential tail in rank–frequency relationships and the negative correlation between phonemic inventory size and relative entropy—can emerge naturally through diachronic sound change. To this end, we develop a stochastic model of phonological evolution that, for the first time, integrates functional load effects with a stabilizing mechanism favoring specific inventory sizes. Using information-theoretic entropy and rank–frequency analyses, the model successfully reproduces the observed phoneme distribution patterns and their negative correlation with inventory size found in real-world languages. These findings demonstrate that such macro-level statistical regularities can spontaneously arise from diachronic processes without explicit optimization, offering an evolutionary explanation for the universality of phonological structure.

Technology Category

Natural Language Processing: Lexical Semantics and MorphologyMachine Learning: Evolutionary LearningCognitive Modeling & Cognitive Systems: Analogy

Application Category

Web Mining and Content Analysis: Models for Web evolutionGraph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphsUser Modeling, Personalization and Recommendation: User modeling and simulation for interactive and conversational systems

Abstract

Phoneme frequency distributions exhibit robust statistical regularities across languages, including exponential-tailed rank-frequency patterns and a negative relationship between phonemic inventory size and the relative entropy of the distribution. The origin of these patterns remains largely unexplained. In this paper, we investigate whether they can arise as consequences of the historical processes that shape phonological systems. We introduce a stochastic model of phonological change and simulate the diachronic evolution of phoneme inventories. A naïve version of the model reproduces the general shape of phoneme rank-frequency distributions but fails to capture other empirical properties. Extending the model with two additional assumptions -- an effect related to functional load and a stabilising tendency toward a preferred inventory size -- yields simulations that match both the observed distributions and the negative relationship between inventory size and relative entropy. These results suggest that some statistical regularities of phonological systems may arise as natural consequences of diachronic sound change rather than from explicit optimisation or compensatory mechanisms.

Problem

• phoneme frequency distributions
• diachronic emergence
• statistical regularities
• phonological systems
• relative entropy

Innovation

• stochastic model
• diachronic phonological change
• phoneme frequency distribution
• functional load
• relative entropy