# Interactions Among Morphology, Word Order, and Syntactic Directionality: Evidence from 55 Languages

## TL;DR

This study explores how language structure balances predictability and flexibility across 55 languages, showing that richer morphology supports more head-final structures.

## Contribution

Quantitative evidence that syntactic directionality is more closely tied to morphological complexity than surface word order.

## Key findings

- Morphological richness weakly correlates with word order entropy and is not a robust predictor after correction.
- Languages with rich morphology favor head-final structures, while minimally inflected languages prefer head-initial patterns.
- Languages balance redundancy and flexibility to optimize information transmission.

## Abstract

This study investigates interactions among morphology, word order, and syntactic directionality across 55 languages from 11 families. We quantify morphological richness (moving-average mean size of paradigm), word order flexibility (entropy), and syntactic directionality (dependency direction), linking linguistic structure to information-theoretic principles. Analyses show that morphological richness is only weakly related to word order entropy and does not provide a robust predictor after statistical correction. Rich morphology facilitates the predictability of syntactic functions. Languages with richer morphology consistently favor head-final structures, whereas minimally inflected languages lean toward head-initial patterns, indicating that syntactic directionality is more closely associated with morphological complexity than with surface word order. Overall, the findings indicate that languages maintain a balance between redundancy and flexibility in optimizing information transmission, providing quantitative evidence for efficiency-driven trade-offs in human language.