Accepting Preposition-Stranding under Sluicing Cross-linguistically; a Noisy-Channel Approach Emilia Molimpakis UCL PhD Linguistics 2 I, Emilia Molimpakis, confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. E. Molimpakis (May, 2019) 3 Abstract This thesis investigates the representation and processing of sluicing, a type of ellipsis where an interrogative CP is reduced to its initial wh-element (the remnant), e.g. Mary danced with someone, but I can't remember (with) who. It is debated whether remnants from within a PP (with who) must appear with this P or whether they can appear without it (`P- stranding'). Existing theoretical literature (Merchant, 2001; a.o.) argues that only languages allowing overt CPs to move wh-elements without their embedding P will allow P-stranding remnants (P-Stranding Generalisation/PSG). Anecdotally, many languages appear to defy this pattern, allowing P-stranding remnants despite disallowing P-stranding overtly. None of these examples, however, are supported by adequate experimental evidence, nor offer a cross-linguistically generalisable explanation. This thesis addresses both these issues. Novel large-scale acceptability data show that both Greek and German, previously proposed robust PSG-examples, do indeed defy it. This behaviour is explained by proposing ellipsis is a type of `noisy channel' (Shannon, 1948; Gibson, Bergen & Piantadosi, 2013), through which the parser must estimate the probability of the intended (elided) message. The parser simultaneously considers the prior likelihood of the intended message (a remnant as part of a full PP) as well as the likelihood of this message being corrupted through `noise' (a deleted P). P-stranding is thus considered a form of deletion, given deletion has been shown to be a likely corruption in noisy channels. A series of reading time studies aimed at supporting this noisy channel model in online processing found results overall consistent with this approach, but also discovered previous work on the processing of sluicing was inaccurate in concluding its active prediction by the parser. Collectively, the work argues for a theory of sluicing involving syntactic structure at the e-site together with sluicing being treated as a noisy channel by the parser. 4 Impact Statement This thesis investigates the topic of ellipsis, a unique linguistic phenomenon that is prolific across all languages. Under ellipsis (1a), meaning is successfully transmitted in the absence of overt linguistic input (i.e. (1b) is understood). (1) a. Someone was at the door yesterday, but I don't know who. b. Someone was at the door yesterday, but I don't know who was at the door yes- terday. All language learners succeed in comprehending ellipsis, despite the absence of overt data to guide them. This indicates that the learner must somehow recover meaning from the sentential context. This process has been argued to reflect innate cognitive biases driving not only language learning, but successful information conveyance, more generally. Be it during learning or in the adult processor, the key question is what contextual information is retrieved and how to fill in the gap under ellipsis? The answer to this question would provide invaluable information not only to the field of theoretical linguistics and language acquisition, but also to that of philosophy, cognitive science, information theory, natural language processing and machine learning, as it would help explain what the human brain considers critical for successful and efficient information transfer. In examining instances of successful information conveyance despite various inconsistencies in the elliptical signal, we would also gain information on the number and type of inconsistencies the human brain is willing to overlook in order to achieve successful communication. Finally, given one of the markers of cognitive decline in elderly populations and neurodegenerative disorders is problematic information identification and retainment, understanding how ellipsis works as a phenomenon and how such populations comprehend and produce it could provide us with an additional tool to help identify the extent and progression of such degradation patterns. Despite ellipsis featuring prominently in syntactic and psycholinguistic literature over the past five decades, there is still great debate as to exactly what information is relevant to its success and how this information is conveyed. Two main theoretical camps exist: one argues the e-site contains full syntactic structure that conveys meaning without being pronounced; and the second that meaning is retrieved without such structure being present at the e-site. Deciding between these two views has been complicated by data behaving both consistently and inconsistently with unpronounced structure at the e-site. This thesis provides valuable evidence towards adjudicating between these two views and addresses two key gaps in the ellipsis literature. Firstly, it provides novel, adequately powered and controlled web-based cross-linguistic acceptability datasets that speak to the debate on structure within the e-site. In extension, a methodological guide for adapting and implementing similar experiments 5 in other languages is provided. Secondly, this thesis offers a cohesive, cross-linguistically generalisable interdisciplinary account of ellipsis. Drawing on both the fields of theoretical syntax and information theory, it argues that there is structure at the site of ellipsis but that our imperfect memory system acts as a noisy channel allowing constrained structural infidelities according to precise informational criteria. Collectively, this work presents the most extensive interdisciplinary exploration of ellipsis to date. 6 Acknowledgements To list all the people and events that have shaped the course of my PhD and the writing of this thesis would be too much for any reader to handle. Ironically, however, the greatest ac- knowledgements, those that should go without saying, are also those that are too important to leave out. First of all, I would like to thank my amazing parents. There are no words to express how grateful I am for the love and support you have given me without question in every step I have taken throughout my life. Our daily conversations have diminished any obstacle I have ever faced and I know I would not have made it this far without them. This thesis is dedicated to you. Thank you, of course, to my supervisors, Andrea and Klaus. Your input has been vital to all the ideas I have had and the experiments I have run from MSc to PhD. To Andrea; thank you for making me an experimentalist who will not accept any result without an accom- panying graph; but also for all our conversations on any subject, for your constructive but kind criticism and your belief in me. To Klaus; thank you for introducing me to the subject of sluicing and convincing me to undertake this PhD. Thank you also for your enthusiasm in all my ideas and for every syntax discussion that has helped push my boundaries. You are polar opposites of each other and it is your combined support and guidance that has made me the academic I am today. Thank you to Jason Merchant for giving me the opportunity to visit the University of Chicago and - together with Anastasia - making me feel so welcome; for all the in-depth discussions, exceptional insight and feedback on my ideas. To Masaya Yoshida, thank you for welcoming me into your lab, for being an overseas mentor and for all the valuable discussions in both person and via Google Hangouts. Thank you to Elena, for every frivolous and serious discussion. You have proven to be one of my dearest friends and I know I can talk to you about anything. And last, but the opposite of least, to Toby. You are the calm to my storm and I could not imagine my life without you. Contents 1 Sluicing and its theories 15 1.1 Introduction . 15 1.1.1 What is sluicing? . 15 1.1.2 What are the main features of sluicing? . 16 1.2 Theories of Sluicing . 19 1.2.1 Most Prominent Syntactic Theories of Sluicing . 20 1.2.2 PF-Deletion and the Amelioration of Islands, a First Account . 22 1.2.3 LF-Copying and Sprouting . 24 1.2.4 PF-Deletion Revisited . 28 1.2.5 Pointer or Anaphor Account . 32 1.3 P-Stranding under Sluicing in Non-P-Stranding Languages . 37 1.3.1 Two Classes of Explanation . 37 1.3.2 PF-Deletion in spite of P-Stranding . 38 1.3.3 P-Stranding therefore No PF-Deletion . 49 1.3.4 Conclusion and the Cases of Greek and German . 53 2 Cross-linguistic Acceptability Judgement Data 57 2.1 Experiment 1: P-Stranding under Regular Sluicing . 57 2.1.1 Experimental Outline, Aim and Predictions . 57 2.1.2 Methods . 64 2.1.3 Results . 73 2.1.4 Discussion . 80 2.2 Experiment 2: P-Stranding out of Islands under Sluicing . 81 2.2.1 Experimental Outline, Aim and Predictions . 81 2.2.2 Methods . 89 2.2.3 Materials . 89 2.2.4 Results . 91 2.2.5 Discussion . 97 2.3 Experiment 3: P-Stranding under Contrast Sluicing . 99 7 8 CONTENTS 2.3.1 Experimental Outline, Aim and Predictions . 99 2.3.2 Methods . 101 2.3.3 Materials . 101 2.3.4 Results . 104 2.3.5 Discussion . 107 2.4 General Discussion for all Greek Acceptability Judgement Studies . 107 2.5 Experiment 4: P-Stranding under Sluicing in German . 113 2.5.1 Experimental Outline, Aim and Predictions . 113 2.5.2 Methods . 116 2.5.3 Results . 122 2.5.4 Discussion . 135 2.6 General Discussion of both Greek and German data . 139 2.6.1 P-stranding via an Alternative Source . 140 2.6.2 P-Stranding as a Grammatical Illusion .