Published online by Cambridge University Press: 01 January 2026
A prominent principle in explaining a range of word-order regularities is dependency locality, which minimizes the linear distances (dependency lengths) between a head and its dependents. However, it remains unclear to what extent language users in fact observe locality when producing sentences under diverse conditions of cross-categorical harmony (such as the placement of verbal and nominal heads on the same vs. different sides of their dependents), dependency direction (head-final vs. head-initial), and parallel vs. hierarchical dependency structures (e.g. multiple adjectives dependent on the same head vs. nested genitive dependents). Using forty-five dependency-annotated corpora of diverse languages, we find that after controlling for harmony and conditioning on dependency types, dependency-length minimization (DLM) is inversely correlated with the overall presence of head-final dependencies. This anti-DLM effect in sentences with more head-final dependencies is specifically associated with an accumulation of dependents in parallel structures and with disharmonic orders in hierarchical structures. We propose a detailed interpretation of these results and tentatively suggest a role for a probabilistic principle that favors embedding head-initial (e.g. VO) structures inside equally head-initial and thereby length-minimizing structures (e.g. relative clauses after the head noun), while head-final (OV) structures have a less pronounced preference for harmony and DLM. This is in line with earlier findings in research on the Greenbergian word-order universals and with a probabilistic version of what has been suggested more recently as the FINAL-OVER-FINAL CONDITION.
This research was supported in part by the Ph.D. grant from the China Scholarship Council (201606320224) and the Postdoc mobility grant from the Swiss National Science Foundation (P500PH_202882) to Yingqi Jing. Damián E. Blasi acknowledges funding from the Branco Weiss Fellowship, administered by the ETH Zurich. We are grateful to the many colleagues who helped us, in particular Lena A. Jäger, Paola Merlo, Paul Widmer, Carlos Gómez-Rodríguez, Kellen Parker van Dam, Yoko Yamazaki, and Arezoo Zandy, and to the associate editors (Shravan Vasishth and Titus von der Malsburg) and the referees for helpful comments. Author contributions: JY, DB, and BB designed the research; JY and BB undertook the theoretical framing; JY and DB produced the random baselines and performed the statistical analysis; and all authors discussed the results and contributed to the final version of the paper.