Ecole´ doctorale Lettres, Langues, Linguistique et Arts Linguistic Complexity and Information: Quantitative Approaches THESIS presented and publicly defended on October 20, 2015 for the degree of Doctor of the University of Lyon in Language Sciences by Yoon Mi OH Jury composition Referees: Prof. Bart de Boer Vrije Universiteit Brussel, Belgium Prof. Bernd M¨obius Universit¨atdes Saarlandes, Germany Examiners: Dr. Christophe Coup´e CNRS & Universit´ede Lyon, France Dr. Christine Meunier CNRS & Aix-Marseille Universit´e,France Dr. Fran¸coisPellegrino CNRS & Universit´ede Lyon, France (Thesis supervisor) Laboratoire Dynamique du Langage | CNRS - Universit´eLumi`ereLyon 2 (UMR 5596) Mis en page avec la classe thesul. Acknowledgements I would like to express my deepest gratitude to my supervisor François Pellegrino for his patient guidance and trust which provided me a lot of support and encouragement for accomplishing my thesis. He has been a role model for me in many aspects, especially with his consideration for others as a director and not to mention his insightful advices. I have been extremely fortunate to work with him who always replied and suggested solutions to so many questions and difficulties I had during my PhD years and I would not have been able to finish this thesis without his help. I am deeply indebted and grateful to Christophe Coupé for his valuable advices and all the works which enriched my thesis, and to Egidio Marsico for so many things: from his precious advices to his warm-hearted help which made me feel at home throughout my stay at the laboratory. I feel myself very lucky to have worked with three warm-hearted colleagues, François, Christophe, and Egidio and I heartily appreciate this perfect trio lyonnais for their patience and confidence and for all the meetings and discussions which were always harmonious and stimulating. I am also highly grateful to the rest of my thesis committee, Bart de Boer, Bernd Möbius, and Christine Meunier for their time, attention, and valuable comments on my dissertation. Especially, I would like to thank Bernd Möbius and the other members of the Phonetics and Phonology group at Saarland University (Bistra, Cristina, Erika, Frank, Jeanine, Jürgen, and Zofia) for giving me a wonderful opportunity to collaborate on their project and their warm welcome. Being a member of the laboratory of Dynamique du Langage was one of the best and unforgettable experiences in my life. Many thanks to Nathalie for her warm and invalu- able support and advices which enormously helped and encouraged me throughout my lab life, to Linda and Sophie for their kind help, to Seb for his patient guidance with programming, to Christian for all the fun board games at lunch, to Emilie for her pre- cious help correcting my French, to Esteban, Geny, Rozenn, and Soraya for their good i vibes in our office, to Agathe, Françoise, Hadrien, Jennifer, Ludivine, Maïa, and Marie for social gatherings outside the lab, and all the other members of the laboratory for the great atmosphere at the lab. This thesis could not have been done without the help of colleagues and native speak- ers who helped me during data collection and analysis. I am especially grateful to Anna, Borja, Frédéric, Gabriella, Hannu, Jànos, Jean-Léopold, Jordi, Laurent, Maja, Miyuki, Pither, Sakal, and Stéphane for their precious help with translation and data collection. I would also like to thank Ramon Ferrer-i-Cancho for his precious advices during my short stay in Barcelona. My heartfelt gratitudes go to my family and friends in Korea who have been there for giving me a lot of support. I thank my parents for their unconditional love, my sister and brother for their affection, my aunt Jinhee for her refreshing energy, and Yunhee, Bitna, and Hyesoo, for their friendship regardless of distance. This work was supported by the LABEX ASLAN (ANR-10-LABX-0081) of Université de Lyon, within the program “Investissements d’Avenir” (ANR-11-IDEX-0007) operated by the French National Research Agency (ANR). ii To my parents iii iv Abstract The main goal of using language is to transmit information. One of the fundamental ques- tions in linguistics concerns the way how information is conveyed by means of language in human communication. So far many researchers have supported the uniform information density (UID) hypothesis asserting that due to channel capacity, speakers tend to encode information strategi- cally in order to achieve uniform rate of information conveyed per linguistic unit. In this study, it is assumed that the encoding strategy of information during speech communication results from complex interaction among neurocognitive, linguistic, and sociolinguistic factors in the frame- work of complex adaptive system. In particular, this thesis aims to find general cross-language tendencies of information encoding and language structure at three different levels of analysis (i.e. macrosystemic, mesosystemic, and microsystemic levels), by using multilingual parallel oral and text corpora from a quantitative and typological perspective. In this study, language is defined as a complex adaptive system which is regulated by the phenomenon of self-organization, where the first research question comes from: “How do languages exhibiting various speech rates and information density transmit information on average?”. It is assumed that the average information density per linguistic unit varies during communication but would be compensated by the average speech rate. Several notions of the Information theory are used as measures for quantifying information content and the result of the first study shows that the average information rate (i.e. the average amount of information conveyed per second) is relatively stable within a limited range of variation among the 18 languages studied. While the first study corresponds to an analysis of self-organization at the macrosystemic level, the second study deals with linguistic subsystems such as phonology and morphology and thus, covers an analysis at the mesosystemic level. It investigates interactions between phono- logical and morphological modules by means of the measures of linguistic complexity of these modules. The goal is to examine whether the equal complexity hypothesis holds true at the mesosystemic level. The result exhibits a negative correlation between morphological and phono- logical complexity in the 14 languages and supports the equal complexity hypothesis from a holistic typological perspective. The third study investigates the internal organization of phonological subsystems by means of functional load (FL) at the microsystemic level. The relative contributions of phonological subsystems (segments, stress, and tones) are quantitatively computed by estimating their role of lexical strategies and are compared in 2 tonal and 7 non-tonal languages. Furthermore, the internal FL distribution of vocalic and consonantal subsystems is analyzed cross-linguistically in the 9 languages. The result highlights the importance of tone system in lexical distinctions and indicates that only a few salient high-FL contrasts are observed in the uneven FL distributions of subsystems in the 9 languages. This thesis therefore attempts to provide empirical and quantitative studies at the three different levels of analysis, which exhibit general tendencies among languages and provide insight into the phenomenon of self-organization. Keywords: complex adaptive system, functional load, information rate, Information theory, language universals, linguistic complexity, quantitative approach, self-organization. v Résumé La communication humaine vise principalement à transmettre de l’information par le bi- ais de l’utilisation de langues. Plusieurs chercheurs ont soutenu l’hypothèse selon laquelle les limites de la capacité du canal de transmission amènent les locuteurs de chaque langue à en- coder l’information de manière à obtenir une répartition uniforme de l’information entre les unités linguistiques utilisées. Dans nos recherches, la stratégie d’encodage de l’information en communication parlée est conçue comme résultant de l’interaction complexe de facteurs neu- rocognitifs, linguistiques, et sociolinguistiques et nos travaux s’inscrivent donc dans le cadre des systèmes adaptatifs complexes. Plus précisément, cette thèse vise à mettre en évidence les ten- dances générales, translinguistiques, guidant l’encodage de l’information en tenant compte de la structure des langues à trois niveaux d’analyse (macrosystémique, mésosystémique, et mi- crosystémique). Notre étude s’appuie ainsi sur des corpus oraux et textuels multilingues dans une double perspective quantitative et typologique. Dans cette recherche, la langue est définie comme un système adaptatif complexe, régulé par le phénomène d’auto-organisation, qui motive une première question de recherche : “Comment les langues présentant des débits de parole et des densités d’information variés transmettent- elles les informations en moyenne ?”. L’hypothèse défendue propose que la densité moyenne d’information par unité linguistique varie au cours de la communication, mais est compensée par le débit moyen de la parole. Plusieurs notions issues de la théorie de l’information ont inspiré notre manière de quantifier le contenu de l’information et le résultat de la première étude montre que le débit moyen d’information (i.e. la quantité moyenne d’information transmise par seconde) est relativement stable dans une fourchette limitée de variation parmi les 18 langues étudiées. Alors que la première