{ "paper_id": "P83-1016", "header": { "generated_with": "S2ORC 1.0.0", "date_generated": "2023-01-19T09:19:28.639372Z" }, "title": "A Framework for Processing Partially Free Word Order*", "authors": [ { "first": "Hans", "middle": [], "last": "Uszkoreit", "suffix": "", "affiliation": {}, "email": "" } ], "year": "", "venue": null, "identifiers": {}, "abstract": "The partially free word order in German belongs to the class of phenomena in natttral language that require a close interaction between syntax and pragmatics. Several competing principles, which are based on syntactic and on discourse information, determine the [ineac order of noun phrases. A solution to problems of this sort is a prerequisite for high-quality language generation. The linguistic framework of Generalized Phrase Structure Grammar offers tools for dealing with-word order variation. Some slight modifications to the framework allow for an analysis of the German data that incorporates just the right, degree of interaction between syntactic and pragmatic components and that can account for conflicting ordering statements.", "pdf_parse": { "paper_id": "P83-1016", "_pdf_hash": "", "abstract": [ { "text": "The partially free word order in German belongs to the class of phenomena in natttral language that require a close interaction between syntax and pragmatics. Several competing principles, which are based on syntactic and on discourse information, determine the [ineac order of noun phrases. A solution to problems of this sort is a prerequisite for high-quality language generation. The linguistic framework of Generalized Phrase Structure Grammar offers tools for dealing with-word order variation. Some slight modifications to the framework allow for an analysis of the German data that incorporates just the right, degree of interaction between syntactic and pragmatic components and that can account for conflicting ordering statements.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Abstract", "sec_num": null } ], "body_text": [ { "text": "The relatively free order of major phrasal constituents in German belongs to the class of natural-language phenomena that require a closer interaction of syntax and pragmatics than is usually accounted for in formal linguistic frameworks. Computational linguists who pay attention to both syntax and pragmatics will find that analyses of such phenomena can provide valuable data for the design of systems that integrate these linguist ic components.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "I. Introduction", "sec_num": null }, { "text": "German represents a good test case because the role of pragmatics in governing word order is much greater than in English while the role syntax plays is greater than in some of the so-called free-word-order languages like Warlpiri. The German data are well attested and thoroughly discussed in the descriptive literature The fact that English and German are closely related makes it easier to assess these data and to draw parallels.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "I. Introduction", "sec_num": null }, { "text": "The .~imple analysis presented here for dealing with free word order in German syntax is based on the linguistic framework of Generalized Phrase Structure Grammar (GPSG}, especially on its Immediate Dominance/Linear Precedence formalism {ID/LP), and complements an earlier treatment of German word order) The framework is slightly modified to accommodate the relevant class of word order regularities.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "I. Introduction", "sec_num": null }, { "text": "The syntactic framework presented in this paper is not hound to any particular theory of discourse processing; it enables syntax to interact with whatever formal model of pragmatics one might want to implement. A brief discussion of the framework's implication~ for computational implementation centers Upon the problem of the status of metagrammatical devices.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "I. Introduction", "sec_num": null }, { "text": "German word order is essentially fixed: however, there is some freedom in the ordering of major phrasal categories like NPs and adverbial phrases -for example, in the linear order of subject (SUB J), direct object (DOBJ), and indirect object (lOB J) with respect to one another. All six permutations of these three constituents are possible for sentences like (In). Two are given as {Ib) and (It).", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "The Problem", "sec_num": "2." }, { "text": "(la) Dann hatte der Doktor dem Mann die Pille gegeben.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "The Problem", "sec_num": "2." }, { "text": "Then had the doctor the man the pill given (lb) Dann hatte dec Doktor die Pille dem Mann gegeben. Then had the doctor the pill the man given (It) Dann hatte die Pille der Doktor dem Mann gegeben. Then had the pill the doctor the man given All permutations have the same truth conditional meaning, which can be paraphrased in English as: Then the doctor gave the man the pill.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "The Problem", "sec_num": "2." }, { "text": "There are several basic principles that influence the ordering of the three major NPs:", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "The Problem", "sec_num": "2." }, { "text": "\u2022 The unmarked order is SUBJ-iOBJ-DOBJ", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "The Problem", "sec_num": "2." }, { "text": "\u2022 Comment (or focus) follows non-comments * Personal pronouns precede other NPs", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "The Problem", "sec_num": "2." }, { "text": "\u2022 Light constituents precede heavy constituents, *This rese.'trch was supported by the National Science Foundation Grant [ST-RI03$50, The views and conclusions expressed in this paper are those ,,r the :tutbor and should not be interpreted as representative of the views of the Nati.,nal Science Foundation or the United States government. I have benefited fr,~rn discussions with and comments from Barbara Grosz, Fernand,, Pcreira. Jane Robinson. and Stuart Shieber. tThe best overview of the current GPSG framework can be found in Gazdar and Pullum (1982) . For :t description of the II)/LP format refer to Gazdar and Pullum (Ig8l} and Klein (1983) , for the ID/LP treatment of German t,, tszkoreit (]g82a. lgB2b} and Nerbonne (Ig82).", "cite_spans": [ { "start": 533, "end": 557, "text": "Gazdar and Pullum (1982)", "ref_id": null }, { "start": 609, "end": 650, "text": "Gazdar and Pullum (Ig8l} and Klein (1983)", "ref_id": null } ], "ref_spans": [], "eq_spans": [], "section": "The Problem", "sec_num": "2." }, { "text": "The order in (la) is based on the unmarked order, (lb) would be appropriate in a discourse situation that makes the man the focus of the sentence, and (1c) is an acceptable sentence if both doctor and man are focussed upon. l use focus here in the sense of comment, the part of the sentence that contains new important information. (lc) could be uttered as an answer to someone who inquires about both the giver and recipient of the pill (for example, with the question: Who gave whom the pill?l. The most complete description of the ordering principles, especially of the conflict between the unmarked order and the topic-commeni, relation, can be found in Lenerz (1977) .", "cite_spans": [ { "start": 658, "end": 671, "text": "Lenerz (1977)", "ref_id": "BIBREF10" } ], "ref_spans": [], "eq_spans": [], "section": "The Problem", "sec_num": "2." }, { "text": "Syntactic as well as pragmatic information is needed to determine the right word order; the unmarked-order principle is obviously a syntactic statement, whereas the topiccomment order principle requires access to discourse information. \u00b0, Sometimes different ordering principles make contradictory predictions. Example (lb) violates the unmarked-order principle; (In) is acceptable even if dem Mann [the man] is the focus of the sentence~ 3", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Implications for Processing Models", "sec_num": "3." }, { "text": "The interaction of ordering variability and pragmatics can be found in many languages and not only in so-called free-wordorder languages. Consider the following two English sentences: (2a) I will talk to him after lunch about the offer. (2b) I will talk to him about the offer after lunch.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Implications for Processing Models", "sec_num": "3." }, { "text": "Most semantic frameworks would assign the same truthconditional meaning to (2a) and (2b), but there are discourse situations in which one is more appropriate than the other. (2a) can answer a que~-tion about the topic of a planned afternoon meeting, but is much less likely to occur after an order to mention the offer as soon as possible. 4", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Implications for Processing Models", "sec_num": "3." }, { "text": "Formal linguistic theories have traditionally assumed the existence of rather independent components for syntax, semantics, and pragmatics, s Linguistics not only could afford this idealization but has probably temporarily benefited from it. However, if the idealization is carried over to the computational implementation of a framework, it can have adverse effects on the efficiency of the resulting system. Peters. 1979) , discourse representations (Kamp, If80) and Situati~,n Semantics ( Barwise and Perry. 1981) narrows the gap between .,,.'mantics and pragmatics.", "cite_spans": [ { "start": 410, "end": 423, "text": "Peters. 1979)", "ref_id": "BIBREF8" }, { "start": 452, "end": 458, "text": "(Kamp,", "ref_id": null }, { "start": 459, "end": 464, "text": "If80)", "ref_id": null }, { "start": 492, "end": 516, "text": "Barwise and Perry. 1981)", "ref_id": "BIBREF0" } ], "ref_spans": [], "eq_spans": [], "section": "Implications for Processing Models", "sec_num": "3." }, { "text": "If we as.~ume that a language generation system should be able to generate all grammatical word orders and if we further assume that, every generated order should be appropriate to the given discourse situation, then a truly nonintegrated system, i.e., a system whose semantic, syntactic, and pragmatic components apply in sequence, has to be inel~cient. The syntax will first generate all possibilities, after which the pragmatic component will have to select the appropriate variant. To do so, this component will also need access to syntactic information.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Implications for Processing Models", "sec_num": "3." }, { "text": "In an integrated model, much unnecessary work can be saved if the syntax refrains from using rules that introduce pragmatically inappropriate orders. A truly integrated model can discard improper parses very early during parsing, thereby considerably reducing the amount of syntactic processing.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Implications for Processing Models", "sec_num": "3." }, { "text": "The question of integrating grammatical components is a linguistic problem. Any reasonable solution for an integration of syntax and pragmatics has to depend on linguistic findings about the interaction of syntactic and pragmatic phenomena. An integrated implementation of any theory that does not account for this interaction will either augment the theory or neglect the linguistic facts.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Implications for Processing Models", "sec_num": "3." }, { "text": "By supporting integrated implementations, the framework and analysis to be proposed below fulfill an important condition for effcient treatment of partially free word order.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Implications for Processing Models", "sec_num": "3." }, { "text": "The theory of GPSG is based on the assumption that nat ural languages can be generated by context-free phrase structure (CF-PS) grammars. As we know, such a grammar is bound to exhibit a high degree of redundancy and, consequently, is not the right formalism for encoding many of the linguistic generalizations a framework for natural language is expected to express. However. the presumption is that it is possible to give a condensed inductive definition of the CF-PS grammar, which contains various components for encoding the linguistic regt,laritics and which can be interpreted as a metagrammar, i.e.. a grammar for generating the actual CF-PS grammar.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Tile Framework of CPSG in ID/LP Format", "sec_num": "4.1" }, { "text": "A GPSG can be defined as a two-leveJ grammar containing a metagrammar and an object grammar. The object grammar combines {CF-PS} syntax and model-theoretic semantics. Its rules are ordered triples (n. r. t) where n is an integer (the rule number}, r is a CF-PS rule. and t is the tramlationoft.he rule, its denotation represented in some version of intensional logic. The translation t is actually an operation that maps the translation of the children nodes into the translation of t.he parent. The nonterminals of r are complex symbols, subsets of a finite set of syntactic features or -as in the latest version of the theory (Gazd:w and Pullum, 1982) -feature trees of finite size. The rules o/' the obJect grammar are interpreted as tree-admissability conditions.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Tile Framework of CPSG in ID/LP Format", "sec_num": "4.1" }, { "text": "The metagrammar consists of four different kinds of rules that are used by three major components to generate the object grammar in a stepwise fashion. Figure {3 ) illustrates the basic structure of a GPSG metagrammar.", "cite_spans": [], "ref_spans": [ { "start": 152, "end": 161, "text": "Figure {3", "ref_id": null } ], "eq_spans": [], "section": "Tile Framework of CPSG in ID/LP Format", "sec_num": "4.1" }, { "text": "(3)", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Tile Framework of CPSG in ID/LP Format", "sec_num": "4.1" }, { "text": "{Basic Rules ~N~ IDR doubles)j/ Application~ [ Metarule (IDR doubles) Rule Extension I i IDR triples) I binearization .' l ~{bjeet-G rammar~'X~ F-PS Rules),~/ Metaxules )", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Tile Framework of CPSG in ID/LP Format", "sec_num": "4.1" }, { "text": "~Rule Ext. Princpls).", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Tile Framework of CPSG in ID/LP Format", "sec_num": "4.1" }, { "text": "First. there is a set of banjo rules. Basic rules are immediate domi.a.ce rule (IDR) double~, ordered pairs < n,i >, where n is the rule number and i is an [DR.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "LP rules )", "sec_num": null }, { "text": "1DRs closely resemble CF-PS rules, but, whereas the CF-PS rule \"1 --6t 6..... 6. contains information about both immediate dominance and linear precedence in the subtree to be accepted, the corresponding IDR \"~ --6t, /f~. ..... /f. encodes only information about immediate dominance. The order of the right-hand-side symbols, which are separated in IDRs by commas, has no significance.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "LP rules )", "sec_num": null }, { "text": "Metarule Application, maps [DR doubles to other IDR doubles. For this purpose, metaxules, which are the second kind of rules are applied to basic rules and then to the output of metarule applications to generate more IDR doubles. Metarules are relations between sets of IDRs and are written as A = B, where A and B are rule templates. The metarute can be read as: If there is an IDR double of kind A, then there is also an IDR double of kind /3. In each case the rule number is copied from A to /3. s .Several metarules can apply in the derivation of a single II)R double; however, the principle of Finite Closure, defined by Thompson (1982}, allows every metarule to apply only once in the derivational history of each IDR double. The invocation of this principle avoids the derivation of infinite rule sets, in-6Rule number might he a misleading term for n because this copying :~.ssigns the s~me integer to the whole class of rules that were derived from the ~ame basic rules. This rule number propagation is a prerequisite for the