Unni Cathrine Eiken February 2005

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2.2 Finding meaning in the context “You shall know a word by the company it keeps!” Firth (1957, p. 179) “The meaning of entities, and the meaning of grammatical relations among them, is related to the restriction of combinations of these entities relative to other entities.” Harris (1968) 2.2.1 The distributional approach The semantic meaning of a word is often readily suggested from the lexical context in which it occurs. This is an idea fronted by many scholars, starting with Firth (1957) and Harris (1968). Human beings use the context of a word in the process of deciding the semantic meaning of the word. When encountering an ambiguous word, the language user has a finite number of possible meanings to consider. By examining the environment that the ambiguous word exists in, the language user finds clues toward deciding which of the possible meanings that are applicable. The same mechanism applies when a language user is confronted with a novel word; by observing the usage of the word, preferably over several instances, a human being is able to induce the semantic meaning from the setting the word occurs in. This is in accordance with the Distributional Hypothesis as proposed by Harris (1968) and contributes to explaining the fact that humans rarely have problems identifying for example what an ambiguous word means, or what entity in the discourse a pronoun refers to. The fact that properties in a word’s linguistic environment can contain information about the meaning of the word is a useful tool for the semantic comparison of words. A word which is used within a limited thematic domain is likely to be used in a sense specific to the contextual setting, or domain, in which it occurs. This entails that the linguistic environment in which the word exists also gives information about the meaning of the word. Words that appear in the same linguistic setting in texts that describe the same theme may have similar or related meanings as well. Texts belonging to the same domain will to some extent contain information about the same things, and as such also contain semantically similar words which are used in similar ways. Following this line of thought, it should be possible to gain relevant information about which words to expect in specific positions in a text by way of looking at the context patterns they should fit into. Thus, words that occur in limited-domain texts can be classified relative to how they combine with each other. The idea that the contextual environment can give clues about the semantic meaning of a word is clearly not a new one, considering the quotes of Firth and Harris in the introduction to this 24
section. The theory dates back to the empiricists of the mid-twentieth century. Linguistic theory in the first half of the twentieth century was to a large degree predominated by empiricism. Linguistic thought, particularly in the United States, but also in Europe, was strongly influenced by the positivism of the behaviourist philosophy. Bloomfield is regarded as one of the chief advocates of linguistic positivism, and his interpretation of linguistics predominated American linguistics in the 1930s and 1940s (Robbins 1997, p. 237). The positivistic/behaviouristic view on linguistic science put emphasis on the observable. Reliable facts could only be found through objective observation of data, and only phenomena which could be empirically experienced by any observer were considered valid data for further analysis. Robbins states that the favoured model of description of the time was that of distribution; for some linguists the notion of linguistic description coincided with the statement of distributional relations (Robbins 1997, p. 239). He also attributes the fact that there was little emphasis on the study of semantics in the early twentieth century to Bloomfield’s dismissal of the possibilities of an empirically based study of this field. Since the analysis of meaning requires non-linguistic knowledge as well, semantic analysis was termed less ideal for empiricist methods. While the study of semantics previously had aimed at creating an exhaustive description of what is referred to by a linguistic entity, Firth represents a challenge to this way of thinking. His “contextual theory of language” introduced a move in semantics, toward a statement of meaning as a function of how words are used (Robbins 1997, p. 247). Together with Harris, Firth represents the distributional approach to finding semantic meaning. Within this approach, meaning is treated as semantic functions related to contexts of situation. This way of analysing meaning is data-driven in the same sense as empiricist approaches in other fields of linguistics and is strongly connected to the positivistic philosophy of science predominant in this time. However, using bottom-up methods as a means to formulate theories of linguistics is a direction that was more or less abandoned after Chomsky’s criticism of the structuralist approaches. Chomsky challenged the philosophical and scientific foundation of the Bloomfieldian canon through his proposal of the transformationalgenerative grammar. He dismissed the behaviouristic approach to language as the unacceptable product of the strong empiricism of the Bloomfieldian behaviourist school. The shift from empiricism to rationalism marks an important turning point in linguistic theory (Robbins 1997, p. 260). Botley and McEnery state that Chomsky, and the generation of linguists following his theories, represent a knowledge-driven approach with the goal of formulating linguistic theories (Botley and McEnery 2000, p. 24). 25
Page 1 and 2: University of Bergen Section for li
Page 3 and 4: Preface The project presented in th
Page 5 and 6: Table of Contents 1 INTRODUCTION AN
Page 7 and 8: 1 Introduction and problem statemen
Page 9 and 10: patterns found in a text collection
Page 11 and 12: The results obtained in this projec
Page 13 and 14: The term anaphor describes a lingui
Page 15 and 16: 2.1.1.1 Discourse representation th
Page 17 and 18: eferring to BT. The NP which is lin
Page 19 and 20: esolution system will not be able t
Page 21 and 22: (2- 12) REC SUBJ EXIST OBJ IND-OBJ
Page 23 and 24: Figure 1 17
Page 25 and 26: means that the algorithm would prop
Page 27 and 28: for an overview). Many of these sys
Page 29: (2- 15) a. Politiet etterlyste i da
Page 33 and 34: 2.2.2 Different types of context So
Page 35 and 36: neighbours. For example, a target w
Page 37 and 38: with it. Selectional constraints al
Page 39 and 40: 3 From text to EPAS - the extractio
Page 41 and 42: 3.2 Predicate-argument structures "
Page 43 and 44: speaker flexibility with regards to
Page 45 and 46: and woman occur together both in su
Page 47 and 48: occur with. Arguments which are unl
Page 49 and 50: 3.3.1 NorGram in outline Norsk komp
Page 51 and 52: Figure 3 The most useful structure
Page 53 and 54: 3.4 Altering the source As already
Page 55 and 56: (3- 12) (3- 13) Politiet leter ette
Page 57 and 58: ARG1 and ARG2 arrays display a valu
Page 59 and 60: (3- 20) Anne Slåtten bodde i et st
Page 61 and 62: value and highly desirable. As such
Page 63 and 64: this project, this can be interpret
Page 65 and 66: The process of classifying the cons
Page 67 and 68: There are several different distanc
Page 69 and 70: . ankomme,etterforsker,?,? ankomme,
Page 71 and 72: Test 2 Training set: EPAS_arg1 with
Page 73 and 74: The training and test material was
Page 75 and 76: • level 0: words which co-occur w
Page 77 and 78: (4- 9) avklare,obduksjon,? bede-om,
Page 79 and 80: (4-10) below shows the output for t
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In the introduction to this chapter
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the EPAS can be used in the classif
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exemption of jobbe-utfra, none of t
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antecedent for (4-15a). In the case
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Figure 7 Interestingly enough, howe
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When testing on knowledge-dependent
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Firth, J. R. (1957): A synopsis of
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Appendix A: Ekstraktor.pl - algorit
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finnARG2(); This function has exact
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#legger lest linje inn i @prt derso
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sub fjernEP{ #fjerner elementer fra
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} splice(@ARGx); $imax = @ARG3ep; @
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} else{ } } } push(@liste, $ARG0ep[
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101 Appendix C: the EPAS list 23-å
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103 obdusere,,kvinne observere,,23-
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Appendix D: Text aligned with EPAS
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eventualiteter. Vi varslet Kripos.
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Etterforskerne har flere observasjo
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# Subrutine som tar inn argumentnum
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Appendix F: POS-based structures SE
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Vi har ingen spesiell teori som vi
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Unni Cathrine Eiken February 2005

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