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Rhetorical Structure Theory

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  1. 1. AK DEN İ Z UNIVERSITY ELT MA DISCOURSE ANALYSISRHETORICAL STRUCTURE THEORY Sebahat YILMAZ 20118509716
  2. 2. Outline Definition of RST Why RST Several studies used RST Areas of Application, Applications Principles Relations Relation Types  Subject-Matter Relations  Presentational Relations  Multinuclear Relations  Examples  Other possible Classifications Graphical Representations, Schemas How to do a RST analysis  Examples Some issues Conclusion Implications References
  3. 3. Rhetorical Structure Theory The term rhetoric is often used to mean persuasive techniques found in non-literary texts.
  4. 4. Rhetorical Structure Theory(Mann, Matthiessen, and Thompson ‘89) “Rhetorical Structure Theory can be defined as a theory of text organization that has led to areas of application ahead of discourse analysis and text generation” (Taboada and Mann, 2005) “A linguistic theory of how text “hangs together” (Mann & Thompson, 1983).
  5. 5. Definition of RST It is a linguistically useful method for describing natural texts, characterizing their structure primarily in terms of relations that hold between parts of the text.
  6. 6. Why RST? It defines hierarchic structure in text. It describes the relation between text parts in functional terms, identifying both the transition point of a relation and the extent of the items related. It provides comprehensive analyses rather than selective commentary. It is insensitive to text size, and has been applied to a wide variety of sizes of text.
  7. 7. Several studies used RST Descriptive RST has been used as an analytical tool for a wide range of text types. Noel (1986), for example, shows how it can be used to characterize news broadcasts. Descriptive RST lays a foundation for studies in contrastive rhetoric. Cui’ s analysis of Mandarin and English essay (Cui,1985) is an example. RST is also useful in analyzing narrative discourse. Kumpf (1986) is a study of interlanguage of Japanese and Spanish speakers. Finally, it provides a framework for investigating Relational Prepositions, which are unstated but inferred prepositions that arise from the text structure in the process of interpreting texts. Since coherence depends on these prepositions, RST has been useful in study of text coherence.
  8. 8. Areas of application Computational linguistics Cross-linguistic studies Dialogue and multimedia Discourse analysis, argumentation and writing
  9. 9. Applications Writing research ◦ How are coherent texts created ◦ RST as a training tool to write effective texts Natural Language Generation ◦ Input: communicative goals and semantic representation ◦ Output: text Rhetorical/discourse parsing ◦ Rendering of a text in terms of rhetorical relations ◦ Using signals, mostly discourse markers Corpus analysis ◦ Annotation of text with discourse relations (Carlson et al. 2002) ◦ Application to spoken language (Taboada 2004, and references in Taboada and Mann 2006) Relationship to other discourse phenomena ◦ Between nuclei and co-reference For more applications : ◦ Taboada, Maite and William C. Mann. (2006). Applications of Rhetorical Structure Theory. Discourse Studies, 8 (4), 567-588.
  10. 10. Principles• Coherent texts consist of minimal units, which are linked to each other through rhetorical relations. - Rhetorical relations also known, in other theories, as coherence or discourse relations. • There must be some relation holding among the different parts of the text.
  11. 11. Relations• Most of the relations have two parts:• a nucleus and a set of one or more satellites.• Some spans are more central to the text’s purpose (nuclei), whereas others are secondary (satellites).• The nucleus is necessary but any satellites are optional.• Spans are joined into discourse relations.• Spans that are in a discourse relation may enter into new relations.
  12. 12. Relation Types• Mann and Thompson propose a set of over 20 relations.• They distinguish subject matter relations (informational) and presentational relations (intentional) , a division roughly corresponds to the semantic-pragmatic dichotomy.• There are Multinuclear Relations, as well. If there are nuclei more than one, the relationship is called Multinuclear.
  13. 13. Relation Types Subject matter relations Presentational relations Condition Motivation Circumstance Background Solutionhood Antihesis Volitional Cause Evidence Volitional Result Enablement Non-volitional cause Concession Non-volitional Result Justification Purpose Otherwise Interpretation Evaluation Restatement Summary Sequence Elaboration Contrast
  14. 14. Multinuclear RelationsThere are also multi-nuclear relations: Contrast Joint List Multinuclear restatement Sequence Conjunction Disjunction
  15. 15. Relation TypesSubject Matter RelationsThose whose intended effect is that the hearerrecognize the relation in question.They relate the content of the text spans.
  16. 16. Circumstance It holds between two parts of a text if one of the parts establishes a circumstance or situation, and the other part is interpreted within or relative that circumstance or situation.“Probably the most extreme case of Visitors Fever I have ever witnessed was a few summers ago, when I visited relatives in the Midwest.”
  17. 17. Example: Circumstance“[N] Probably the most extreme case of Visitors Fever I have ever witnessed was a few summers ago, [S] when I visited relatives in the Midwest.” The satellite in a Circumstance relation sets a framework, e.g., a temporal or spatial framework, within which to interpret the nucleus. This function has been grammaticized in English in the form of circumstantial hypotactic clauses (M&T 1987:48)
  18. 18. Elaboration (Set-member,class/instance/whole- part…)N: basic informationS: additional informationJohn likes coffee. He drinks it every day.
  19. 19. Example: Elaboration [Your teacher may tell you lots of ways to keep your eyes from nearsightedness.][Such as keep thirty centimeters from your eyes to the table,][and not to read books when it’s dark.] The second and third clauses are linked through the relationship of ‘joint’ because one is added to the other and jointly modify the first sentence by elaborating its meaning (‘elaboration’).
  20. 20. Contrast MultinuclearS: one alternateOther Span: the other alternate.John likes coffee. Mary hates it.
  21. 21. ExplanationJohn went to the coffee shop. He was sleepy.
  22. 22. Discourse structure John likes coffee They argue a lot con tras t tion e us ca ora Mary hates coffee. elabHe drinks it every day
  23. 23. Sequence Multinuclear Peel oranges, and slice crosswise.• Across sentences: 1. Peel oranges, 2. and slice crosswise. 3. Arrange in a bowl 4. and sprinkle with rum and coconut. 5. Chill until ready to serve
  24. 24. Volitional Cause (a) George Bush supports big business. (b) He’s sure to veto House Bill 1711.
  25. 25. Nonvolutional Cause“Remember all those vegetables you slipped underthe table?Maybe that’s why sparky lived so long.”
  26. 26. Subject Matter Relations Solutionhood: N is a situation or method supporting full or partial satisfaction of the need. S is a question, request, problem, or other expressed need Purpose: S presents goal of the activity in N Nonvolitional-result: N: a situation; S: another situation which is caused by that one, but not by anyone’s deliberate action Condition : S presents precondition for N
  27. 27. Example
  28. 28. Presentational Relations Those whose intended effect is to increasesome inclination in the hearer; such asthe desire to act or the degree of positiveregard for, belief in, or acceptance of thenucleus.More rhetorical in nature. They are meant toachieve some effect on the reader.
  29. 29. Presentational Relations Motivation (increases desire) Background (increases ability) Antithesis (increases positive regard) Evidence (increases belief) Enablement (increases ability) Concession (increases positive regard) Justification (increases acceptance)
  30. 30. Motivation (Mann & Thompson, 1993)Relation name: Motivation• Constraints on N:Presents an action (unrealized with respect to N) in which thehearer is the actor.• Constraints on S: None• Constraints on S+NComprehending S increases the hearers desire to perform theaction presented in N.• Effect:The hearer’s desire to perform the action presented in N isincreased.
  31. 31. MotivationMotivation relates any utterance which expresses the speaker’s desire that the hearer performs some action (the nucleus) with material which will justify the requested action(the satellites).1) Come to the party for the new president.2) There will be lots of good food.• A motivation relation exists between 1 and 2
  32. 32. Motivation S: (a) Come home by 5:00. (b) Then we can go to the hardware store before it closes. (c) That way we can finish the bookshelves tonight. motivation motivation (a) (b) (c)condition (a) (b) condition (c)
  33. 33. Background N: text whose understanding is being facilitated S:text for facilitating understanding
  34. 34. Concession
  35. 35. EvidenceN: claim.S provides evidence for something claimed in N. They know, therefore, that one of the ten people on the island was not a murderer in any sense of the word, and it follows, paradoxically, that that person must logically be the murderer. (Christie 2003:315) The first unit (They know, therefore… any sense of the word) is related to the second unit (and it follows… be the murderer) by means of an ‘evidence’ tie between the first unit and second unit. That is to say, the first unit functions as the evidence fo the second unit. The relations, units and direction of effect are all decided by the analyst (Bateman and Delin 2006:590).
  36. 36. Example: Evidence Constraints on the Nucleus ◦ The reader may not believe N to a degree satisfactory to the writer Constraints on the Satellite ◦ The reader believes S or will find it credible Constraints on the combination of N+S ◦ The reader’s comprehending S increases their belief of N Effect (the intention of the writer) ◦ The reader’s belief of N is increased
  37. 37. Antithesis N: ideas favored by the author S: ideas disfavored by the author
  38. 38. Example: Antithesis Nucleus (spans 2-3) made up of two spans in an Antithesis relation Concession across sentences
  39. 39. Example multinuclear relation
  40. 40. Example
  41. 41.  So long as Conditional To Purpose• What is more Elaboration The text is constructed on a thesis- antithesis relation; first 9 units are thesis, the rest is antithesis.
  42. 42. Other possible classifications Relations that hold outside the text ◦ Condition, Cause, Result vs. those that are only internal to the text ◦ Summary, Elaboration Relations frequently marked by a discourse marker ◦ Concession (although, however); Condition (if, in case) vs. relations that are rarely, or never, marked ◦ Background, Restatement, Interpretation Preferred order of spans: nucleus before satellite ◦ Elaboration – usually first the nucleus (material being elaborated on) and then satellite (extra information) vs. satellite-nucleus ◦ Concession – usually the satellite (the although-type clause or span) before the nucleus
  43. 43. Other classifications are possible, and longer and shorterlists have been proposedRelation names (M&T 1988) Circumstance Antithesis and Concession Solutionhood Antithesis Elaboration Concession Background Condition and Otherwise Enablement and Motivation Condition Enablement Otherwise Motivation Interpretation and Evaluation Evidence and Justify Interpretation Evidence Evaluation Justify Restatement and Summary Relations of Cause Restatement Volitional Cause Summary Non-Volitional Cause Other Relations Volitional Result Sequence Non-Volitional Result Contrast Purpose
  44. 44. More RST relationsRelation Name Nucleus SatelliteAntithesis ideas favored by the author ideas disfavored by the authorBackground text whose understanding is being facilitated text for facilitating understanding text expressing the events or ideas occurring in theCircumstance an interpretive context of situation or time interpretive contextConcession situation affirmed by author situation which is apparently inconsistent but also affirmed by author action or situation whose occurrence results from theCondition conditioning situation occurrence of the conditioning situationElaboration basic information additional informationEnablement an action information intended to aid the reader in performing an actionEvaluation a situation an evaluative comment about the situationEvidence a claim information intended to increase the readerÕ belief in the claim sInterpretation a situation an interpretation of the situationJustify text information supporting the writerÕsright to express the textMotivation an action information intended to increase the readerÕ desire to perform the action sNon-volitional Cause a situation another situation which causes that one, but not by anyoneÕ deliberate action sNon-volitional Result a situation another situation which is caused by that one, but not by anyoneÕsdeliberate actionOtherwise (anti action or situation whose occurrence results from the conditioning situationconditional) lack of occurrence of the conditioning situationPurpose an intended situation the intent behind the situationRestatement a situation a reexpression of the situationSolutionhood a situation or method supporting full or partial a question, request, problem, or other expressed need satisfaction of the needSummary text a short summary of that textVolitional Cause a situation another situation which causes that one, by someoneÕsdeliberate actionVolitional Result a situation another situation which is caused by that one, by someoneÕs deli erate action b
  45. 45. Graphical representation A horizontal linecovers a span of text (possiblymade up of further spans A vertical linesignals the nucleus or nuclei A curverepresents a relation, and the direction of the arrow, the direction of satellite towardsnucleus .
  46. 46. Schemas• They specify how spans of text can co- occur, determining possible RST text structures c ir c u m s ta n c e jo in t c o n tra st m o tiv a tio n e n a b le m e n t sequence sequence
  47. 47. How to do a RST analysis RST provides a systematic way for an analyst to annotate a text.3. Divide the text into units • Unit size may vary, depending on the goals of the analysis • Typically, units are clauses (but not complement clauses)4. Examine each unit, and its neighbours. Is there a clear relation holding between them?5. If yes, then mark that relation (e.g., Condition)6. If not, the unit might be at the boundary of a higher-level relation. Look at relations holding between larger units (spans)7. Continue until all the units in the text are accounted for8. Remember, marking a relation involves satisfying all 4 fields (especially the Effect). The Effect is the plausible intention that the text creator had.
  48. 48. Example An analysis is usually built by reading the text and constructing a diagram that resembles Figure 1. This is a title and summary, appearing at the top of an article in Scientific American magazine (Ramachandran and Anstis, 1986). The original text, broken into numbered units, is:1. [Title:] The Perception of Apparent Motion2. [Abstract:] When the motion of an intermittently seen object is ambiguous,3. the visual system resolves confusion4. by applying some tricks that reflect a built-in knowledge of properties of the physical world. The main way in which one unit becomes connected to another is by adding an RST relation to the diagram
  49. 49. FIGURE 1. Diagram of an RST analysis
  50. 50. Example1) Lactose and Lactase2) Lactose is milk sugar; 3) the enzyme lactase breaks it down.4) For want of lactase most adults cannot digest milk.5) In populations that drink milk the adults have more lactase, perhaps through natural selection.6) Norman Kretchmer, Scientific American, page 70, October 1972.
  51. 51. The text:1) Lactose and Lactase2) Lactose is milk sugar; 3) the enzyme lactase breaks it down.4) For want of lactase most adults cannot digest milk.5) In populations that drink milk the adults have more lactase, perhaps through naturalselection.6) Norman Kretchmer, Scientific American, page 70, October 1972. (http://www.sfu.ca/rst)
  52. 52. Some issues Problems in identifying relations ◦ Judgments are plausibility judgments. Two analysts might differ in their analyses Definitions of units ◦ Vary from researcher to researcher, depending on the level of granularity needed Relations inventory ◦ Many available ◦ Each researcher tends to create their own, but large ones tend to be unmanageable A theory purely of intentions ◦ In contrast with Grosz and Sidner’s (1986), it does not relate structure of discourse to attentional state. On the other hand, it provides a much richer set of relations.
  53. 53. Some Problems with RST(Moore & Pollack 1992) How many Rhetorical Relations are there? How can we use RST in dialogue as well as monologue? RST does not allow for multiple relations holding between parts of a discourse RST does not model overall structure of the discourse
  54. 54. ConclusionThe last twenty years or so of development and use of RST provide us with three types of contributions: a better understanding of text, a conceptual structure of relations and how it relates to coherence, and contribution to a great diversity of work in several fields in which RST is used as a conceptual starting point, far beyond text generation, the initial target (Taboada and Mann, 2005).
  55. 55. Implications RST may be used to provide a general way to describe the relations among clauses in a text, whether or not they are grammatically or lexically signalled; describe or understand the structure of texts, and to link rhetorical structure to other phenomena, such as anaphora or cohesion, and analyze narrative discourse.
  56. 56. References  Alexander,,M., 2009). Rhetorıcal Structure And Reader Manıpulatıon In Agatha Chrıstıe’s Murder On The Orıent Express. (Miscelánea: a journal of english and american studies 39 , 13-27.  Carlson, Lynn, Daniel Marcu and Mary Ellen Okurowski. (2002). RST Discourse Treebank, LDC2002T07 [Corpus]. Philadelphia, PA: Linguistic Data Consortium.  Grosz, Barbara J. and Candace L. Sidner. (1986). Attention, intentions, and the structure of discourse. Computational Linguistics, 12 (3), 175-204.  Gruber H. and Huemer B., (2008). Two Views on Text Structure: Using Rhetorical Structure Theory and Register & Genre Theory in Improving Students’ Academic Writing. Systemic Functional Linguistics in Use. Odense Working Papers in Language and Communication vol. 29  Mann, William C., Christian M.I.M. Matthiessen and Sandra A. Thompson. (1992). Rhetorical Structure Theory and text analysis. In W. C. Mann and S. A. Thompson (Eds.), Discourse Description: Diverse Linguistic Analyses of a Fund- Raising Text (pp. 39-78). Amsterdam and Philadelphia: John Benjamins.  Mann, William C. and Maite Taboada. (2007). RST Web Site. Retrieved July 2008, from http://www.sfu.ca/rst  Mann, William C. and Sandra A. Thompson. (1988). Rhetorical Structure Theory: Toward a functional theory of text organization. Text, 8 (3), 243-281.  Mann, W. C. & Thompson, S. A. 1987. Rhetorical Structure Theory: a Theory of Text Organisation. ISI Reprint Series ISI/RS–87–190. Marina del Rey (CA): Information Sciences Institute.  Skoufaki, S., (2009) An Exploratory Application of Rhetorical Structure Theory to Detect Coherence Errors in L2 English Writing: Possible Implications for Automated WritingEvaluation Software. Computational Linguistics and Chinese Language Processing Vol. 14, No. 2, 181-204  Taboada, Maite. (2004). Building Coherence and Cohesion: Task-Oriented Dialogue in English and Spanish. Amsterdam and Philadelphia: John Benjamins.  Taboada, Maite and William C. Mann. (2006a). Applications of Rhetorical Structure Theory. Discourse Studies, 8 (4), 567-588.• Taboada, Maite and William C. Mann. (2006). Rhetorical Structure Theory: Looking back and moving ahead. Discourse Studies, 8 (3), 423-459.• Yeh C.C. (2004). The Relationship of Cohesion and Coherence: A Contrastive Study of English and Chinese. Journal of Language and Linguistics, Vol. 3 No 2. 243-260.
  57. 57. Thank You

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