LING83600: Context-Free Grammars
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Scaffolding Learning of Language Structures with Visual‐Syntactic Text
UC Irvine UC Irvine Previously Published Works Title Scaffolding learning of language structures with visual-syntactic text formatting Permalink https://escholarship.org/uc/item/6235t25b Journal British Journal of Educational Technology, 50(4) ISSN 0007-1013 Authors Park, Y Xu, Y Collins, P et al. Publication Date 2018 DOI 10.1111/bjet.12689 Peer reviewed eScholarship.org Powered by the California Digital Library University of California British Journal of Educational Technology Vol 0 No 0 2018 1–17 doi:10.1111/bjet.12689 Scaffolding learning of language structures with visual-syntactic text formatting Youngmin Park, Ying Xu , Penelope Collins, George Farkas and Mark Warschauer Youngmin Park is a Lecturer at Pusan National University, Korea. She received her Ph.D. degree from the University of California, Irvine, specializing in Language, Literacy and Technology. Ying Xu is a Ph.D. student at the University of California, Irvine, with a specialization in specializing in Language, Literacy and Technology. Penelope Collins is an associate professor at the University of California, Irvine. Her research examines the development of language and literacy skills for children from linguistically diverse backgrounds. George Farkas is a professor at the University of California, Irvine. He has employed a range of statistical approaches and databases to examine the causes and consequences of reading achievement gap across varying age groups and educational settings. Mark Warschauer is a professor at the University of California, Irvine. He works on a range of research projects related to digital media in education. Address for correspondence: Ying Xu, University of California Irvine, 3200 Education Bldg, Irvine, CA 92697, USA. -
Probabilistic Grammars and Their Applications This Discretion to Pursue Political and Economic Ends
Probabilistic Grammars and their Applications this discretion to pursue political and economic ends. and the Law; Monetary Policy; Multinational Cor- Most experiences, however, suggest the limited power porations; Regulation, Economic Theory of; Regu- of privatization in changing the modes of governance lation: Working Conditions; Smith, Adam (1723–90); which are prevalent in each country’s large private Socialism; Venture Capital companies. Further, those countries which have chosen the mass (voucher) privatization route have done so largely out of necessity and face ongoing efficiency problems as a result. In the UK, a country Bibliography whose privatization policies are often referred to as a Armijo L 1998 Balance sheet or ballot box? Incentives to benchmark, ‘control [of privatized companies] is not privatize in emerging democracies. In: Oxhorn P, Starr P exerted in the forms of threats of take-over or (eds.) The Problematic Relationship between Economic and bankruptcy; nor has it for the most part come from Political Liberalization. Lynne Rienner, Boulder, CO Bishop M, Kay J, Mayer C 1994 Introduction: privatization in direct investor intervention’ (Bishop et al. 1994, p. 11). After the steep rise experienced in the immediate performance. In: Bishop M, Kay J, Mayer C (eds.) Pri ati- zation and Economic Performance. Oxford University Press, aftermath of privatizations, the slow but constant Oxford, UK decline in the number of small shareholders highlights Boubakri N, Cosset J-C 1998 The financial and operating the difficulties in sustaining people’s capitalism in the performance of newly privatized firms: evidence from develop- longer run. In Italy, for example, privatization was ing countries. -
Grammars and Normal Forms
Grammars and Normal Forms Read K & S 3.7. Recognizing Context-Free Languages Two notions of recognition: (1) Say yes or no, just like with FSMs (2) Say yes or no, AND if yes, describe the structure a + b * c Now it's time to worry about extracting structure (and doing so efficiently). Optimizing Context-Free Languages For regular languages: Computation = operation of FSMs. So, Optimization = Operations on FSMs: Conversion to deterministic FSMs Minimization of FSMs For context-free languages: Computation = operation of parsers. So, Optimization = Operations on languages Operations on grammars Parser design Before We Start: Operations on Grammars There are lots of ways to transform grammars so that they are more useful for a particular purpose. the basic idea: 1. Apply transformation 1 to G to get of undesirable property 1. Show that the language generated by G is unchanged. 2. Apply transformation 2 to G to get rid of undesirable property 2. Show that the language generated by G is unchanged AND that undesirable property 1 has not been reintroduced. 3. Continue until the grammar is in the desired form. Examples: • Getting rid of ε rules (nullable rules) • Getting rid of sets of rules with a common initial terminal, e.g., • A → aB, A → aC become A → aD, D → B | C • Conversion to normal forms Lecture Notes 16 Grammars and Normal Forms 1 Normal Forms If you want to design algorithms, it is often useful to have a limited number of input forms that you have to deal with. Normal forms are designed to do just that. -
CS351 Pumping Lemma, Chomsky Normal Form Chomsky Normal
CS351 Pumping Lemma, Chomsky Normal Form Chomsky Normal Form When working with a context-free grammar a simple and useful form is called the Chomsky Normal Form (CNF). A CFG in CNF is one where every rule is of the form: A ! BC A ! a Where a is any terminal and A,B, and C are any variables, except that B and C may not be the start variable. Note that we have two and only two variables on the right hand side of the rule, with the exception that the rule S!ε is permitted where S is the start variable. Theorem: Any context free language may be generated by a context-free grammar in Chomsky normal form. To show how to make this conversion, we will need to do three things: 1. Eliminate all ε rules of the form A!ε 2. Eliminate all unit rules of the form A!B 3. Convert remaining rules into rules of the form A!BC Proof: 1. First add a new start symbol S0 and the rule S0 ! S, where S was the original start symbol. This guarantees that the start symbol doesn’t occur on the right hand side of a rule. 2. Remove all ε rules. Remove a rule A!ε where A is not the start symbol For each occurrence of A on the right-hand side of a rule, add a new rule with that occurrence of A deleted. Ex: R!uAv becomes R!uv This must be done for each occurrence of A, so the rule: R!uAvAw becomes R! uvAw and R! uAvw and R!uvw This step must be repeated until all ε rules are removed, not including the start. -
Chapter 7 Linguistics As a Science of Structure Ryan M
Chapter 7 Linguistics as a science of structure Ryan M. Nefdt University of the Western Cape Generative linguistics has rapidly changed during the course of a relatively short period. This has caused many to question its scientific status as a realist scientific theory (Stokhof & van Lambalgen 2011; Lappin et al. 2000). In this chapter, I argue against this conclusion. Specifically, I claim that the mathematical foundations of the science present a different story below the surface. I agree with critics that due to the major shifts in theory over the past 80 years, linguistics is indeed opened up to the problem of pessimistic meta-induction or radical theory change. However, I further argue that a structural realist approach (Ladyman 1998; French 2006) can save the field from this problem and at the same time capture its structural nature. I discuss particular historical instances of theory change in generative grammar as evidence for this interpretation and finally attempt to extend it beyond the gener- ative tradition to encompass previous frameworks in linguistics. 1 Introduction The generativist revolution in linguistics started in the mid-1950s, inspired in large part by insights from mathematical logic and in particular proof theory. Since then, generative linguistics has become a dominant paradigm, with many connections to both the formal and natural sciences. At the centre of the newly established discipline was the syntactic or formal engine, the structures of which were revealed through modelling grammatical form. The generativist paradigm in linguistics initially relied heavily upon the proof-theoretic techniques intro- duced by Emil Post and other formal logicians to model the form language takes (Tomalin 2006; Pullum 2011; 2013).1 Yet despite these aforementioned formal be- ginnings, the generative theory of linguistics has changed its commitments quite 1Here my focus will largely be on the formal history of generative syntax but I will make some comments on other aspects of linguistics along the way. -
Syntactic Structures and Their Symbiotic Guests. Notes on Analepsis from the Perspective of On- Line Syntax*
Pragmatics 24:3.533-560 (2014) International Pragmatics Association DOI: 10.1075/prag.24.3.05aue SYNTACTIC STRUCTURES AND THEIR SYMBIOTIC GUESTS. NOTES ON ANALEPSIS FROM THE PERSPECTIVE OF ON- LINE SYNTAX* Peter Auer Abstract The empirical focus of this paper is on utterances that re-use syntactic structures from a preceding syntactic unit. Next utterances of this type are usually treated as (coordination) ellipsis. It is argued that from an on-line perspective on spoken syntax, they are better described as structural latency: A grammatical structure already established remains available and can therefore be made use of with one or more of its slots being filled by new material. A variety of cases of this particular kind of conversational symbiosis are discussed. It is argued that they should receive a common treatment. A number of features of the general host/guest relationship are discussed. Keywords: Analepsis; On-line syntax; Structural latency. "Ein Blick in die erste beste Erzählung und eine einfache Ueberlegung muss beweisen, dass jede frühere Aeusserung des Erzählenden die Exposition aller nachfolgenden Prädikate bildet." (Wegener 1885: 46)1 1. Introduction The notion of 'ellipsis' is often regarded with some skepticism by Interactional Linguists - the orientation to 'full' sentences is all too obvious (cf. Selting 1997), and the idea that speakers produce complete sentences just in order to delete some parts of them afterwards surely fails to account for the processual dynamics of sentence production and understanding (cf. Kindt 1985) in time. On the other hand, there can be little doubt that speakers often produce utterance units that could not be understood * I wish to thank Elizabeth Couper-Kuhlen and Susanne Günthner for their helpful comments on a previous version of this paper. -
Generative Linguistics and Neural Networks at 60: Foundation, Friction, and Fusion*
Generative linguistics and neural networks at 60: foundation, friction, and fusion* Joe Pater, University of Massachusetts Amherst October 3, 2018. Abstract. The birthdate of both generative linguistics and neural networks can be taken as 1957, the year of the publication of foundational work by both Noam Chomsky and Frank Rosenblatt. This paper traces the development of these two approaches to cognitive science, from their largely autonomous early development in their first thirty years, through their collision in the 1980s around the past tense debate (Rumelhart and McClelland 1986, Pinker and Prince 1988), and their integration in much subsequent work up to the present. Although this integration has produced a considerable body of results, the continued general gulf between these two lines of research is likely impeding progress in both: on learning in generative linguistics, and on the representation of language in neural modeling. The paper concludes with a brief argument that generative linguistics is unlikely to fulfill its promise of accounting for language learning if it continues to maintain its distance from neural and statistical approaches to learning. 1. Introduction At the beginning of 1957, two men nearing their 29th birthdays published work that laid the foundation for two radically different approaches to cognitive science. One of these men, Noam Chomsky, continues to contribute sixty years later to the field that he founded, generative linguistics. The book he published in 1957, Syntactic Structures, has been ranked as the most influential work in cognitive science from the 20th century.1 The other one, Frank Rosenblatt, had by the late 1960s largely moved on from his research on perceptrons – now called neural networks – and died tragically young in 1971. -
The Logic of Categorial Grammars: Lecture Notes Christian Retoré
The Logic of Categorial Grammars: Lecture Notes Christian Retoré To cite this version: Christian Retoré. The Logic of Categorial Grammars: Lecture Notes. RR-5703, INRIA. 2005, pp.105. inria-00070313 HAL Id: inria-00070313 https://hal.inria.fr/inria-00070313 Submitted on 19 May 2006 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. INSTITUT NATIONAL DE RECHERCHE EN INFORMATIQUE ET EN AUTOMATIQUE The Logic of Categorial Grammars Lecture Notes Christian Retoré N° 5703 Septembre 2005 Thème SYM apport de recherche ISRN INRIA/RR--5703--FR+ENG ISSN 0249-6399 The Logic of Categorial Grammars Lecture Notes Christian Retoré ∗ Thème SYM — Systèmes symboliques Projet Signes Rapport de recherche n° 5703 — Septembre 2005 —105 pages Abstract: These lecture notes present categorial grammars as deductive systems, and include detailed proofs of their main properties. The first chapter deals with Ajdukiewicz and Bar-Hillel categorial grammars (AB grammars), their relation to context-free grammars and their learning algorithms. The second chapter is devoted to the Lambek calculus as a deductive system; the weak equivalence with context free grammars is proved; we also define the mapping from a syntactic analysis to a higher-order logical formula, which describes the seman- tics of the parsed sentence. -
The Chomsky Enigma
Weekly Worker 655 - Thursday January 4 2007 18/08/2010 11:07 Weekly Worker 655 Thursday January 11 2007 Subscribe to the Weekly Worker 18:08:201004:05:2009 The Chomsky home contact enigma action weekly worker respect the unity coalition How is that a powerful critic of US imperialism european social forum has been regarded as a valued asset by the US theory military? In the first of three articles Chris Knight resources of the Radical Anthropology Group begins his what we fight for examination of the life and work of Noam programme Chomsky join Noam Chomsky ranks among the leading intellectual search figures of modern times. He has changed the way we Fighting fund think about what it means to be human, gaining a communist university position in the history of ideas - at least according to On the links his supporters - comparable with that of Galileo, Descartes or Newton. Since launching his intellectual our history assault against the academic orthodoxies of the move 1950s, he has succeeded - almost single-handedly - in revolutionising linguistics and establishing it as a modern science. Our January fund has received an early boost with a handsome Such intellectual victories, however, have come at a £100 donation from comrade GD. cost. The stage was set for the “linguistics wars”1 Which is very handy, as when Chomsky published his first book. He might as circumstances have conspired to well have thrown a bomb. “The extraordinary and force us to change premises - an traumatic impact of the publication of Syntactic expensive business, as readers structures by Noam Chomsky in 1957,” recalls one will know. -
Appendix A: Hierarchy of Grammar Formalisms
Appendix A: Hierarchy of Grammar Formalisms The following figure recalls the language hierarchy that we have developed in the course of the book. '' $$ '' $$ '' $$ ' ' $ $ CFG, 1-MCFG, PDA n n L1 = {a b | n ≥ 0} & % TAG, LIG, CCG, tree-local MCTAG, EPDA n n n ∗ L2 = {a b c | n ≥ 0}, L3 = {ww | w ∈{a, b} } & % 2-LCFRS, 2-MCFG, simple 2-RCG & % 3-LCFRS, 3-MCFG, simple 3-RCG n n n n n ∗ L4 = {a1 a2 a3 a4 a5 | n ≥ 0}, L5 = {www | w ∈{a, b} } & % ... LCFRS, MCFG, simple RCG, MG, set-local MCTAG, finite-copying LFG & % Thread Automata (TA) & % PMCFG 2n L6 = {a | n ≥ 0} & % RCG, simple LMG (= PTIME) & % mildly context-sensitive L. Kallmeyer, Parsing Beyond Context-Free Grammars, Cognitive Technologies, DOI 10.1007/978-3-642-14846-0, c Springer-Verlag Berlin Heidelberg 2010 216 Appendix A For each class the different formalisms and automata that generate/accept exactly the string languages contained in this class are listed. Furthermore, examples of typical languages for this class are added, i.e., of languages that belong to this class while not belonging to the next smaller class in our hier- archy. The inclusions are all proper inclusions, except for the relation between LCFRS and Thread Automata (TA). Here, we do not know whether the in- clusion is a proper one. It is possible that both devices yield the same class of languages. Appendix B: List of Acronyms The following table lists all acronyms that occur in this book. (2,2)-BRCG Binary bottom-up non-erasing RCG with at most two vari- ables per left-hand side argument 2-SA Two-Stack Automaton -
G612310 Syntactic Theory and Analysis
The Openness of Natural Languages Paul M. Postal, New York University e-mail: [email protected] Preface It might seem plausible to the non-specialist who thinks about natural language (NL) that a given NL, NLx, permits one to report linguistic performances, both performances of NLx elements and those of NLs distinct from NLx. By ‘reporting linguistic performances’ I refer to nothing more arcane than forming statements like ‘Amanda just shouted ‘where’s my baby?’’ It might also seem to a non-specialist that NLx permits one to do descriptive linguistics, not only the descriptive linguistics of NLx, but that of other distinct NLs. By ‘doing descriptive linguistics’ I mean nothing more exotic than forming sentences like ‘The German word for ‘air force’ is ‘Luftwaffe’’. But while these non-specialist assumptions might seem not only plausible but self-evidently true, modern linguistics in its dominant instantiation called generative grammar, in fact denies both these claims. Of course, it does this only implicitly and most advocates of generative grammar may be unaware that its doctrines taken literally preclude what any non-specialist would assume possible. Readers not easily accepting this conclusion will find their skepticism addressed in what follows, for a major goal of this study is to justify in detail the claim that generative grammar has the evidently intolerable implications just mentioned. Section 1 Background Near the beginning of the generative grammar movement in linguistics the following claims were made (all emphases mine: PMP): (1)a. Chomsky (1959: 137) “A language is a collection of sentences of finite length all constructed from a finite alphabet (or, where our concern is limited to syntax, a finite vocabulary) of symbols.” b. -
STRUCTURE and STRUCTURALISM in PHILOSOPHY of LANGUAGE and SEMIOTICS by Susan Petrilli
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by ESE - Salento University Publishing STRUCTURE AND STRUCTURALISM IN PHILOSOPHY OF LANGUAGE AND SEMIOTICS by Susan Petrilli Abstract Structuralism covers a broad range of different tendencies in different disciplines over the entire twentieth century. The term structuralism is plurivocal: it is used for different trends from a variety of different scientific fields and may even diverge on the theoretical and methodological levels. This essay examines some of the main trends in structuralism not only in linguistics, but beyond in other areas of research on language and signs, including philosophy of language through to latest developments in semiotics, and most recently biosemiotics. A critical approach to structuralism is proposed for the development of critical structuralism involving such problematics as Marxian proto-structuralism; the intersemiotic transposition of semiotic approaches to linguistic and socio-cultural structures; ontological structuralism and methodological structuralism; the human being as a semiotic animal and a structuralist animal. Le structuralisme couvre un large éventail de tendances différentes dans les différentes disciplines pendant le XXe siècle. Le terme structuralisme est plurivoque: se réfère à des orientations différentes de différents domaines scientifiques, même sur le 44 plan théorique et méthodologique. Cet article examine quelques-unes des principales tendances du structuralisme, non seulement en linguistique,